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CHh/ 



HARVARD UNIVERSITY 

Library of the 

Museum of 

Comparative Zoology 



MUS. COM P. ZOOli 
LIBRARY 



The CANADIAN 



MAYS 1970 

HARV/\H^a 



FIELD-NATURALIST 



Published by THE OTTAWA FIELD-NATURALISTS' CLUB, Ottawa, Canada 





Volume 92, Number 1 



January-March 1978 



The Ottawa Field-Naturalists' Club 

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The Canadian Field-Naturalist 

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Cover: Northern Fulmar photographed by W. A. Montevecchi on 1 June 1977 as it flew off the cliffs of Baccalieu Island. 
Newfoundland where it nested. See Note on page 80. 



THE CANADIAN 
FIELD-NATURALIST 



Volume 92 
1978 



THE OTTAWA FIELD-NATURALISTS' CLUB 

Ottawa Canada 



The Canadian Field-Naturalist 



Volume 92, Number 1 



January-March 1978 



Rearing Atlantic Salmon {Salmo salar) in Fishless 
Lakes of the Matamek River System, Quebec^ 



David M. Rimmer^ and G. Powers 



Department of Biology, University of Waterloo, Waterloo, Ontario 

^Present address: Department of Biology, University of New Brunswick, Fredericton, New Brunswick E3B 5A3 
^Present address: Centre d'Etudes Nordiques, Universite Laval, Quebec, Quebec GIK 7P4 

Rimmer, D. M. and G. Power. 1978. Rearing Atlantic Salmon {Salmo salar) in fishless lakes of the Matamek River system, 
Quebec. Canadian Field-Naturalist 92(1): 1-9. 

An attempt to utilize fishless lakes for producing smolts of Atlantic Salmon {Salmo salar) resuhed in exceptional growth, but 
poor survival and no migration. Ondietsofzooplankton with a high proportion of larvae of Chaoboridae and Chironomidae, 
alevins grew at rates of 0.54-0.67 mm-day~', yearlings attained mean fork lengths of 168 mm, and 3+-year-old fish averaged 
404 mm fork length. These growth rates are greater than any other recorded for Atlantic Salmon in fresh water. Condition 
factors were high, ranging from 1.17 to 1 .60. The findings indicate that Atlantic Salmon can survive and grow well in these 
fishless lakes, but great care must betaken to ensure that survival is good. Also, if this potential management technique is to be 
successfully developed, a solution to the non-migration problem must be found. 

Key Words: Atlantic Salmon, fisheries management, fish introduction. 



Atlantic Salmon {Salmo salar) populations 
will continue to decline from the effects of 
debasement of their environment (Netboy 1974) 
and increased relative fishing pressure 
(Paloheimo and Elson 1974) unless ways are 
found to supplement or replace natural pro- 
duction. In both Norway (Berg 1967) and Britain 
(Harris 1973), fishless lakes and tarns have been 
used with some success to raise salmon smolts. 
The technique offers a possible alternative to 
artificial rearing, which, although highly refined 
(Peterson 1971), has become extremely costly. 
Fishless lakes in the headwaters of the Matamek 
River (Power et al. 1973) offered an opportunity 
to study this management technique in Quebec. 
The lakes contained dense limnetic populations 
of larval Chaoborus spp. (Pope et al. 1973) as 
well as smaller zooplanktonic crustaceans that 
could serve as natural food. Lack of predation 
and interspecific competition were expected to 
lead to high survival and rapid growth of the 
fish. It was anticipated that smoltification, 



'Contribution Number32 of the Matamek Research Station, 
Sept-Iles, Quebec 



which is closely related to size (Elson 1957), 
would occur early in life and it was hoped that 
the smolts would migrate to the sea to supple- 
ment the natural smolt run from the Matamek 
River. This communication presents the results 
of alevin (Balon 1975) planting between 1970 
and 1974 in four fishless lakes. 

Study Areas 

The lakes used in these experiments were 
Gallienne, Randin, Head, and Crosskey (Figure 
1). All lie on the slow-weathering igneous rock of 
the Canadian Shield and are surrounded by 
boreal forest. Selected morphometric char- 
acteristics are given in Table 1. Gallienne and 
Randin are deep lakes with only 13% and 2.5% 
of their surface area, respectively, being less than 
2 m deep. Aquatic vegetation is sparse in all 
lakes and consists of Nuphar, Sparganium, 
Potamogeton, Vallisneria, Ceratophyllum, 
Chara, Lemna, Myriophyllum, and Anacharis 
in that order of abundance. The lake bottoms 
consist of stones, sand, silt, and detritus in 
various proportions around the shores and a 
highly organic gel-Uke silt in the deeper areas. 



1 



The Canadian Field-Naturalist 



Vol. 92 



30' 


Head L. / 


T-T 


1 




i)/P 






Randin Cry<^''"-'2,$^ >> 








L.Gallienne^\^\ -1^ \ 


Sj- 7 ^Crosskey L. 


25' 


■7;Gallienne J . ■ ^^r^ 


-'^^^ upper 

Matamek R. 




Muskrdt R: '; T^- Z^ „ 


? :■■■' 




20' 


'^ — < / Matamek L. 


- 




J \.,--_lower 

J ^-^ Matamek R. 




N 








1 






/ Gulf of ^~V^ 








50° 15' 


/ St. Lawrence 




- 




/ ° 


5 

1 


10 

1 






km 
.i 






1 1 1 


-I 





05' Se-OO' 55' 50' 65°45' 

Figure 1. Portion of the Matamek River system, Quebec 
showing the four study lakes and the Laurentian 
Escarpment. 

A small stream, Randin Creek, offering good 
alevin habitat in the lower reaches, connects 
Lakes Randin and Gallienne. Lake Gallienne 
discharges via Gallienne Creek to Matamek 
Lake, then via the Matamek River to the Gulf of 
St. Lawrence. Head Lake forms the headwaters 
of the Muskrat River which supports a natural 
salmon population in its lower reaches below the 
escarpment. Crosskey Lake is drained by a tiny 
riffle which flows for 400 m before descending 
precipitously down the escarpment to join the 
upper Matamek River. 

Chemical analyses of midsummer water 

Table 1 — Selected morphometrical characteristics of the 
four study lakes 





Gal- 




Cross- 






lienne 


Randin 


key 


Head 


Area (ha) 


39.6 


41.6 


12.0 


12.6 


Altitude (m) 


290 


312 


343 


260 


Volume (m' X 10*) 


3.96 


14.40 


— 


— 


Maximum depth (m) 


44 


70 


17 


11 


Mean depth (m) 


10.9 


34.7 


— 


— 


Shoreline (m X lO') 


5.92 


3.71 


2.52 


1.70 



samples from Gallienne, Randin, and Crosskey 
Lakes are given in Table 2. It is assumed that 
Head Lake is similar. These lakes resemble 
typical Shield lakes as described by Armstrong 
and Schindler (1971). 

Table 2 — Chemical analyses of lake water showing 
midsummer conditions 





Gallienne 


Randin 


Crosskey 


pH 


6.1 





6.3 


Specific conductance^ 


14.5 


13.6 


14.4 


(jumho-cm"' at 25°C) 








Dissolved oxygen (mg-L"') 








surface (1 m) 


8.9 (9.8)" 


— 


8.5 


hypoHmnion (10 m) 


9.3 (7.3)" 


— 


4.2 


Alkalinity (mg-L'' CaCOs) 


2.4 


— 


1.2 


Ca (mg-L"')^ 


0.37 


1.27 


0.70 


Mg (mg-L"')^ 


0.19 


0.36 


0.02 


K (mg-L"')^ 


0.19 


0.12 


0.05 


Na (mg-L"')^ 


0.83 


1.42 


0.36 



'From Pope (1973). 

"in parentheses — 7 March 1974 (under ice). 

Materials and Methods 

Alevins for planting were provided by the 
Provincial Fish Hatchery at Tadoussac, 475 km 
southwest of Matamek. They were progeny of 
wild fish taken near the mouth of the Saguenay 
River, presumably of St. Marguerite River 
stock. The alevins were planted at about 70 
days post-hatch; they had been fed for 2 weeks. 
Transport was by truck to Sept-Iles, taking 
6.5 h, then by helicopter to the planting site, 
taking 15-30 min. Fish were carried in 9-L 
polyethylene sacks at a density of 1 fish per 3 ml 
water. The air space in each sack was enriched 
with oxygen and the sacks were packed in ice in 
an insulated box during the journey. At Lake 
Gallienne, where the helicopter could land, 
alevins were released slowly from a boat; care 
was taken to distribute them as much as possible 
in shallow water and to mix gradually the 
transport and lake water. At the other lakes, 
alevins had to be released quickly from the floats 
or skids of the helicopter. In Lakes Randin and 
Head, planting was over deep open water 
because planting sites were dictated by the 
requirements of the pilot. In Crosskey Lake, 
planting was achieved over shallow water. Table 
3 gives the dates and numbers of alevins released 
into each lake. 

Soon after release alevins were recaptured in 
Lake Gallienne by means of "night-fishing" with 



1978 



RiMMER AND POWER: ATLANTIC SALMON, QUEBEC 



Table 3- 


-Numbers of alevins and release dates 


in the four 






study lakes 






Year 


Gallienne 


Randin 


Crosskey 


Head 


1970 


93 000 
10 June 


31 200 
12 June 


1 


— 


1971 


— 


— 


— 


— 


1972 


24 500 


— 


42 000 


17 500 




16 June 




16 June 


16 June 


1973 


50 500 


16 500 


16 500 


16 500 




22 June 


22 June 


22 June 


22 June 


1974 


16 500 

2 July 


— 


— 


— 


Total 


184 500 


47 700 


58 500 


34 000 



'A dash indicates no planting. 

the use of 300-candle-power lanterns, hand nets, 
and hand seines. Collections were made fort- 
nightly from 21 July to 23 August 1973 in the 
lower section of Randin Creek. In 1974, weekly 
collections were made in Randin Creek and on a 
rocky beach in Lake Gallienne between 21 July 
and 24 August. 

Nylon gillnets, 7.6 X 1.5 m monofilament and 
45.7 X 1.5 m multifilament, were used to retrieve 
yearling and older fish. Stretched mesh sizes of 
the monofilament nets were 13, 19, 25, and 
38 mm and of the multifilament nets 38, 51, 64, 
77, 90, 103, and 116 mm. Most nets were 
bottom-set from shore to a maximum depth of 
9 m. Lackey (1970) has shown that Atlantic 
Salmon are to be found in this depth stratum 
when they are living in lakes. In Lakes Gallienne 
and Head, the nets were rotated to ensure that all 
netting locations were fished by all sizes of net; 
nets were not rotated in Lake Randin. In 
Crosskey Lake, the same pattern of net dis- 
tribution was used in August and September to 
simplify a tentative population estimate. The 
fishing effort for 1973 and 1974 is summarized in 
Table 4. Trap nets were tried, but were with- 
drawn owing to lack of suitable setting sites, 



ineffectiveness of the traps, and isolation of 
some of the lakes. 

To monitor possible smolt movement from 
Lake Gallienne, two barrier traps were con- 
structed in Gallienne Creek during 1973. One, 
800 m downstream from the lake, was 
operational from 1 1 June; the other, 350 m 
downstream from the lake, from 13 June. 
Surface water temperature in the lake was 8°C at 
this time. Both traps were operated until 23 
August. In 1974, only the 350-m trap was 
operated from 15 June when the lake surface 
water temperature had reached 10°C. This trap 
was removed on 22 August. 

Data collected from retrieved fish included 
fork length (mm), weight (g), scales, and 
stomachs. Stomachs were preserved in 5% 
formalin and later opened to remove the 
contents of the cardiac portion. Food items were 
identified to family, and diet was described using 
the "frequency of occurrence" method. 

Results 

Preliminary gillnet samples in 1971 and 1972 
led to considerable optimism about the success 
of alevin planting in Lake Gallienne. In 1971, 82 
fish were captured with 218 net-h of effort 
between 26 July and 26 August. The average size 
of these l+-fish was 168 mm (range 117- 
272 mm). The following year, 31 fish collected in 
June, aged 2+, averaged 202 mm and four fish 
taken in August averaged 325 mm (range 115- 
376 mm). Total effort was 230 net-h. The more 
detailed follow-up work in 1973 and 1974, 
however, showed that the initial optimism was 
not warranted, at least where survival was 
concerned. Gillnet captures were always 
sporadic and meagre regardless of frequent 
rotation and adjustment of the nets. Table 5 
summarizes monthly fishing effort, catch, and 
catch per unit effort in the four experimental 



Table 4 — Net details of retrieval operations in the four study lakes during June-September 1973-1974 



Year 





Number 


Number of 


Net size' 


Total 


Lake 


of nets 


locations 


(mm) 


time (h) 


Gallienne 


15 


36 


13-103 


4500 


Randin 


7 


7 


25-51 


777 


Head 


11 


14 


19-38 


914 


Gallienne 


10 


15 


38-116 


2550 


Crosskey 


8 


8 


38-64 


728 



1973 



1974 



'Stretched mesh in 13-mm intervals beyond 38 mm. 



The Canadian Field-Naturalist 



Vol. 92 



Table 5 — Monthly effort, catch, and catch per unit effort (CUE) in the four study lakes during 1973-1974 



Lake 



Effort 


(net-h) 






Catch (number 




CUE (fishnet-h"') 


June July 


Aug. 


Sept. 


June July 


Aug. 


Sept. 


June 


July 


Aug. Sept. 


220 516 


3186 







26 


51 




0.00 


0.05 


0.03 — 


576 734 


1053 


— 


1 


37 


90 


— 


0.02 


0.05 


0.08 — 


— 777 


— 


— 


— 





— 


— 


— 


0.00 


— — 


— — 


914 


— 


— 


— 





— 


— 


— 


0.00 — 


_ _ 


440 


288 


_ 


_ 


97 


23 


_ 


_ 


0.22 0.08 



Gallienne 

1973 

1974 
Randin 

1973 
Head 

1973 
Crosskey 

1974 



lakes during 1973 and 1974; one net-hour 
represents one unit of effort. Accurate estimates 
of the numbers of salmon remaining in the lakes 
were impossible because failure of the trap nets 
precluded any marking experiment and because 
gillnet returns revealed no pattern to which a 
catch statistics method could be applied. One 
possible exception was Crosskey Lake in 1974 
where, when the data for August and September 
catches were used and the Leslie method 
outlined in Ricker ( 1 975, p. 1 50) was applied, the 
population of salmon remaining in the lake was 
tentatively estimated at 106 yearlings and 51 
two-year-olds. It should be noted that the water 
temperature had fallen to 8°C in September, 
which may have biased the results, and 127 fish 
were removed from the lake during sampling. 
All indications are that few salmon remained in 
any lake and perhaps no fish were left in Lakes 
Randin and Head. 

Scales from all sampling years (1970-1974) 
were used to describe the growth of 322 fish 
recovered from Lake Gallienne and 120 from 
Crosskey Lake. Interpretation of the scales was 
easy. Figure 2 A shows a typical scale of a 3+ fish 
(1970 planting) from Lake Gallienne. The early 
years of growth on such scales can readily be 
distinguished from the parr growth of Matamek 
River fish (Figure 2B). The freshwater zone of 
the sea-run fish (comprising three years of 
growth) is equivalent in size to the first-year zone 
of the Lake Gallienne salmon. Planted fish that 
have spent at least the first year in fishless lakes 
can readily be separated from wild stock from 
the Matamek River. 

Growth of alevins during the first summer 
after planting was analyzed using mean fork 
lengths of samples retrieved from Randin Creek 



and Lake Gallienne. Growth was Unear over the 
summer and can be described by the following 
equations: 

Randin Creek 1973 v = 24.3 + 0.53x 

Randin Creek 1974 y- 24.7 + 0.54x 

Lake Gallienne 1974 v = 25.8 + 0.67x 

where v - fork length (mm) and x - days past 
planting. These equations convert to growth 
rates of 0.53 mm-d"' and 0.54 mm-d~' in Randin 
Creek during 1973 and 1974 respectively and 
0.67 mm-d~' in Lake Gallienne. Annual growth 
of older fish in Lakes Gallienne and Crosskey is 
shown in Figure 3. These curves are based on fish 
retrieved in August and September from 
Crosskey Lake (length-age relationship was the 
same for the two sampling periods) and 
recaptures between June and September of the 
1970 year class in Lake Gallienne; the 1970 year 
class data from Lake Gallienne provided the 
most complete results, but growth offish planted 
in other years was similar. The mean condition 
factors (K) of the fish calculated for different life 
history stages are given in Table 6. 

Analysis of the diet of first-summer fish taken 
in Randin Creek (July-August) showed 
chironomid larvae and imagos to be the most 
important components. Baetid nymphs and 
daphnids were also consumed throughout the 
summer, but to a lesser extent. Other organisms 
appeared occasionally in the diet. In the lake, 
chironomids were replaced by chaoborid larvae; 
cladocerans were also important particularly in 
July when polyphemids and daphnids were 
occasionally predominant. The diet of the older 
fish in Lakes Gallienne and Crosskey is sum- 
marized in Table 7. Chaoborid larvae were 
always the major food item in both lakes. Other 
items were periodically important, but their 



1978 



RiMMER AND POWER: ATLANTIC SALMON, QUEBEC 




Z-^ 2mm 



A, Lake Galienne salmon (fork 
length, 483 mm) showing 
three annulae indicating an 
age of 3+. 



B, Matamek River salmon 
(fork length, 510 mm) 
showing three freshwater 
annulae and one seawater 
annulus indicating a total 
age o( 4+. 



Figure 2. Scales of Atlantic Salmon from the Matamek River system. 



appearance in the diet probably indicates only 
the opportunistic nature of salmon feeding 
behavior. Negligible surface feeding occurred. 
All stomachs containing food (over 80%) were 
filled to distension. 



In the lake environment, recognition of life 
history stages, parr, smolt, and adult, presents 
some difficulties particularly as dead fish tend to 
revert to a more parr-like appearance. It was 
important for this study to recognize, if at all 



Table 6 — Mean condition factors 


(K)' 


of 


salmon 


at various 


life stages 


in 


Lake 


Gallienne and Cross 


key Lake 




Galienne (July-Aug.) 








Crosskey (Aug. 


-Sept.) 


Parr 






Smolt 




Adult 




Parr 


Adult 


Number 36 
K 1.60 
Standard deviation 0.32 






31 
1.46 
0.20 




10 
1.16 
0.16 






60 
1.41 
0.07 


61 
1.17 
0.13 



'K = I/N S( '^ ^^ V W = weight in grams, L = fork length in millimetres, N = number of fish in sample. 



The Canadian Field-Naturalist 



Vol. 92 



400 


~ 




(10) • 


300 


- 


/ 


o(47) / 
/ 
/ / 


200 


/ 
/ 

(73)o^^ 

(82) 


- 


/f(35) 
Lake Gallienne • • 


100 


1 




Crosskey Lake o o 

1 1 



V 2+ 3* 

Age 
(years) 

Figure 3. Growth of salmon in Lake Gallienne (1970 year 
class) and Crosskey Lake. Numbers in parentheses 
are sample sizes. Vertical bars are 95% confidence 
intervals. 

possible, these stages because true migration, as 
distinct from dispersal, could be expected only at 
the smolt stage. During 1973 and 1974, 35 smolts 
(mean fork length, 183 mm) were caught 
during July in Lake Gallienne; all were yearlings. 
In August 1973 and 1974, we took 44 yearlings 
(mean fork length, 194 mm) of smolt-like 
appearance, having a definite silver sheen and 
dark fins, but with faint parr bars and red spots. 
No smolts were taken from Crosskey Lake, but 
this could have been because fishing had been 
done late in the summer. Eleven out of 73 
yearlings taken from Crosskey Lake were clas- 
sified as adults on the basis of external 
appearance. These were very large (mean fork 
length, 235 mm). All 2+ fish from Crosskey Lake 
were adults. In Lakes Gallienne and Crosskey, 
all fish possessd only immature gonads. 

No evidence of migration of smolts was 



obtained during the study. No salmon were 
captured in the barrier traps in Gallienne Creek, 
but the effectiveness of the traps in capturing fish 
was verified by the frequent capture of resident 
brook trout {Salvelinus fontinalis) below the 
escarpment. In 1974, the trap operated through- 
out a large spring spate which occurred at water 
temperatures ideal for smolt migration (10°C) 
The scales of anadromous salmon returning to 
the Matamek River since 1972 (the first possible 
year for returns as 1+ smolts and one-sea-winter 
fish from the 1970 plantings) were examined for 
the characteristic growth patterns of the lake 
fish, but none was found in 154 samples. 

Discussion and Conclusions 

The number of salmon alevins that survived 
transport and were able to establish themselves 
in the fishless lakes was very low. In the two lakes 
where planting was done over deep water, 
Randin and Head, no survivors were retrieved. 
The problem of survival does not appear to be 
related to the suitability of the lakes as habitat, 
for they all conform to criteria known to be 
suitable for Atlantic Salmon (see e.g., Havey 
and Warner 1970; Cooper 1940) and the few 
survivors grew exceptionally well. It was evident 
that the alevins were exhausted and disoriented 
after the long journey from Tadoussac. 
Experiments conducted to investigate the extent 
of their debility showed greatly reduced 

Table 7 — Diet composition of yearling and older salmon 

in Lake Gallienne (July-August 1973-1974) and Crosskey 

Lake (August-September 1974). Numbers indicate % 

occurrence 





Gallienne 


Crosskey 


Insecta 






Chaoboridae larvae 


59.90 


62.00 


pupae 


0.01 


0.00 


Corixidae adults 


39.50 


25.20 


, Baetidae nymphs 


12.30 


0.05 


Phryganeidae larvae 


0.03 


0.03 


adults 


0.03 


16.80 


Libellulidae nymphs 


0.02 


0.03 


Aeshnidae nymphs 


0.02 


0.04 


Coenagrionidae nymphs 


11.30 


41.20 


Ephemeridae larvae 


0.02 


0.0 1 


Notonectidae adults 


0.02 


0.03 


Crustacea 






Daphnidae adults 


0.01 


11.20 


Empty 


9.00 


0.04 


Number of fish 


195 


107 



1978 



RiMMER AND POWER: ATLANTIC SALMON, QUEBEC 



buoyancy and pronounced sounding behavior 
(Rimmer 1975). It is quite possible that the 
alevins released over deep water vanished into 
the depths where cold temperatures (< 4°C) 
would halt normal activity (Allen 1941) and 
great pressure caused mortality (Bishai 1960). 
The use of highly sensitive echo-sounding 
equipment may be the easiest way of clarifying 
the uncertainties of post-planting survival. 

The outstanding growth of the fish in this 
Ashless habitat is evident when compared with 
data in the literature, most of them from more 
temperate environments where growth condi- 
tions could be expected to be better. Allen (1941) 
recorded a growth rate for young-of-the-year of 
0.40 mm-d"^for Halkirk Burn and 0.38 mm-d~' 
for the River Eden, both figures much less than 
those for Randin Creek (0.53 and 0.54 mmd"') 
or Lake Gallienne (0.67 mm-d"'). Rapid growth 
continues, resulting in 3+ fish in fresh water that 
are not much smaller than one-sea-winter fish of 
wild Matamek stock. A comparison of this 
growth with that of selected introduced and wild 
populations is provided in Table 8. Even fish 
planted as alevins in fishless lakes in Wales, 
which grew much faster than natural stocks (c./.. 
Table 8), did not grow as fast as the fish in the 
present study. 

The rapid growth of the fish in the Matamek 
lakes may be explained in part by the absence of 
interspecific and low intraspecific competition 
because of the low density of survivors. Higher 
densities of fish in the lakes would eventually 
suppress the growth rate as food resources 
became limiting. The most striking feature of the 



results is the enormous growth potential of 
young Atlantic Salmon which, even in a 
relatively severe physical environment (as the 
North Shore of the Gulf of St. Lawrence must be 
considered), can be expressed in the absence of 
competition and with suitable food. Chaoborid 
larvae provide the bulk of the diet offish beyond 
the alevin stage and these were present in the 
lakes in very high densities. Pope et al. (1973) 
recorded densities of 477/ m- in Lake Gallienne 
and 979/ m2 in Crosskey Lake. Planktonic 
organisms were apparently sufficient to satisfy 
the food requirements of the salmon because 
very little surface-feeding occurred. On this 
planktonic diet the fish grew very fat and K 
factors (Table 6) far exceeded those of wild 
populations which, except for maturing male 
parr, are usually close to unity (Hoar 1939; 
Power 1969). 

No evidence of smolt migration was found 
during the study. The presence in Lake Gallienne 
of large fish bearing an appearance inter- 
mediate between parr and smolt during August 
suggests that these fish were smolts earlier in the 
year, but had not migrated. Evropeitseva (1962) 
has reported smolts reverting to their parr livery 
if they did not go to sea shortly after 
smoltification. It is not uncommon when rearing 
salmon in fishless lakes to have some fish 
become residual, but it appears rare that all 
should stay. In Loch Kinardochy, 4.47% of the 
1965 planting and 41.85% of the 1967 planting 
failed to migrate (Harris 1973). Jones and Evans 
(1962) found post-smolts up to the age of 6+ in 
Llyn Dyrnogydd, but apparently most fish 



Table 8 — Age-group lengths (mm) of young salmon of various origin from selected bodies of water 





Originally 

fishless 


Salmon 




Ai 


'fi 






Location 


origin 


1 + 


2+ 


3+ 


4+ 


Source 


Lake Gallienne, Quebec 


Yes 


Introduced 


168.3 


216.7 


404.1 


_ 


This study 


Crosskey Lake, Quebec 


Yes 


Introduced 


176.9 


313.3 


— 


— 


This study 


Llyn Cilan, Wales 


Yes 


Introduced 


113.7 


— 


— 


— 


Sinha and Evans (1969) 


Llyn Dyrnogydd, Wales 


Yes 


Introduced 


136.0 


165.0 


201.0 


— 


Jones and Evans (1962) 


Llyn Teyrn, Wales 


Yes 


Introduced 


104.0 


158.0 


— 


— 


Jones and Evans (1962) 


Lough Knader, Ireland 


No 


Introduced 


43.7 


119.8 


191.0 


— 


Hewetson (1963) 


Gambo Pond, Newfoundland 


No 


Ouananiche 


80.0 


157.0 


205.0 


322.0 


Leggett and Power (1969) 


Terra Nova River, Nfld. 


No 


Ouananiche 


99.0 


113.0 


176.0 


216.0 


Andrews (1966) 


River Forss, Scotland 


No 


Sea-running 


112.0 


129.0 


— 


— 


Frost (1950) 


Sinclair Burn, Scotland 


No 


Sea-running 


88.0 


107.0 


— 


— 


Allen (1941) 


Breivikelva, Norway 


No 


Sea-running 


74.0 


99.0 


109.0 


124.0 


Power (1973) 


Matamek River, Quebec 


No 


Sea-running 


77.0 


113.0 


133.0 


— 


Schiefer(1969) 



The Canadian Field-Naturalist 



Vol. 92 



migrated from the lake at age 2+ or 3+. Berg 
(1967) has reported residual salmon in Nor- 
wegian lakes, some even showing evidence of 
spawning. The critical question here is: what 
causes residual behavior? Is migration blocked 
because suitable stimuli are not present in the 
lakes or do the fish resemble smolts mor- 
phologically without being physiologically met- 
amorphosed? If migration is somehow con- 
nected with a requirement for greater food 
resources to support greater growth, increasing 
the density of fish in the lakes by improving 
survival should induce migration. 

If the potential of fishless lakes as rearing 
areas for salmon smolts is to be realized, answers 
to the above questions are needed. It is also 
apparent from our own experience that much 
more needs to be known about factors that 
influence the mortality of alevins both during 
transport and after planting in a lentic environ- 
ment. An increase in survivorship is the prime 
problem to be overcome if this management 
technique is to be developed. 

Acknowledgments 

This work was funded by the Woods Hole 
Oceanographic Institution and the University of 
Waterloo. We thank D. Semple, G. Lacroix, and 
J. A. Dolan for field assistance. We gratefully 
acknowledge the co-operation of le Ministere du 
Tourisme, de la Chasse et de la Peche du Quebec 
and the assistance of the staff of la Pisciculture 
Provincial, Tadoussac, Quebec. R. J. Gibson 
kindly read and criticized the manuscript. 

Literature Cited 

Allen, K. R. 1941. Studies on the biology of the early 
stages of the salmon {Salmo salar). 3. Growth in the 
Thurso River system, Caithness. Journal of Animal 
Ecology 10: 273-295. 

Andrews, C. W. 1966. Landlocked Atlantic Salmon 
(Salmo salar L.) in the Terra Nova River system, 
Newfoundland. Canadian Field-Naturalist 80: 101 109. 

Armstrong, F.A.J, and D. W. Schindler. 1971. Pre- 
liminary characterization of waters in the Experimental 
Lakes Area, northwestern Ontario. Journal of the 
Fisheries Research Board of Canada 28: 171-187. 

Balon, E. K. 1975. Terminology of intervals in fish de- 
velopment. Journal of the Fisheries Research Board of 
Canada 32: 1663-1670. 

Berg, M. 1967. Utsettinger av laksyngel i vatn og tjern. 
Fisk og Fiskestell 4. 63 pp. 

Bishai, H. M. 1960. The effect of pressure on the sur- 
vival and distribution of larval and young fish. Journal 
du Conseil 25: 292-311. 



Cooper, G. P. 1940. A biological survey of the Rangeley 
Lakes with special reference to trout and salmon. 
Maine Department of Inland Fish and Game, Fish 
Survey Report 3. 182 pp. 

Elson, P. F. 1957. The importance of size in the change 
from parr to smolt in the Atlantic salmon. Canadian 
Fish-CulturaHst 21: 1-6. 

Evropeitseva, N. V. 1962. Comparative analysis of the 
desmoltification process among the young of different 
forms of Atlantic Salmon. Uchenye Zapiski Lenin- 
gradskogo Ordena Lenina Gosudarstvennogo Nauk 311: 
46-73. (Translated from Russian, Fisheries Research 
Board of Canada Translation Series 413. 24 pp.) 

Frost, W. E. 1950. The growth and food of young salmon 
(Salmo salar) and trout (S. trutta) in the River 
Forss, Caithness. Journal of Animal Ecology 19: 147-158. 

Harris, G. S. 1973. Rearing smolts in mountain lakes to 
supplement salmon stocks. International Atlantic Salmon 
Foundation Special Publication Series 4: 237-253. 

Havey, K. A. and K.Warner. 1970. The landlocked salmon 
(Salmo salar): its life history and management in 
Maine. Maine Department of Inland Fish and Game, 
Augusta. 129 pp. 

Hewetson, A. 1963. Salmon rearing experiments in Lough 
Knader, a small lake in Co. Donegal, Ireland. Report 
on the Sea and Inland Fisheries, 1962. 8 pp. 

Hoar, W. S. 1939. The weight-length relationship of At- 
lantic Salmon. Journal of the Fisheries Research 
Board of Canada 4: 441-460. 

Jones, J. W. and H. Evans. 1962. Salmon rearing in 
mountain tarns — a preliminary report. Proceedings of 
the Zoological Society of London 138: 499-515. 

Lackey, R. T. 1970. Seasonal depth distribution of land- 
locked Atlantic Salmon, Brook Trout, landlocked 
Alewives and American Smelt in a small lake. Journal 
of the Fisheries Research Board of Canada 27: 1656-1661. 

Leggett, W. C. and G. Power. 1969. Differences between 
two populations of landlocked Atlantic Salmon (Salmo 
salar) in Newfoundland. Journal of the Fisheries 
Research Board of Canada 26: 1585-1596. 

Netboy, A. 1974. The salmon: their fight for survival. 
Houghton Mifflin, Boston. 611 pp. 

Paloheimo, J. E. and P. F. Elson. 1974. Reduction of 
Atlantic Salmon (Salmo salar) catches in Canada 
attributed to the Greenland fishery. Journal of the 
Fisheries Research Board of Canada 31: 1467-1480. 

Peterson, H. H. 1971. SmoU rearing methods, equipment 
and techniques used successfully in Sweden. Inter- 
national Atlantic Salmon Foundation Special Publi- 
cation Series 2: 32-62. 

Pope, G. F. 1973. The influence of fish in causing vari- 
ations in the zooplankton communities of lakes in the 
Matamek River system. Ph.D. thesis. University of 
Waterloo, Waterloo, Ontario. 173 pp. 

Pope, G. F., J. C. H. Carter, and G. Power. 1973. The 
influence of fish on the distribution of Chaoborus 
spp. (Diptera) and density of larvae in the Matamek 
River system, Quebec. Transactions of the American 
Fisheries Society 102: 707-714. 

Power, G. 1969. The salmon of Ungava Bay. Arctic 
Institute of North America Technical Paper Number 22. 
72 pp. 

Power, G. 1973. Estimates of age, growth, standing crop 



1978 



RIMMER AND POWER: ATLANTIC SALMON, QUEBEC 



and production of salmonids in some north Norwegian 
rivers and streams. Report of the Institute of Freshwater 
Research, Drottningholm 53: 78-111. 

Power, G., G. F. Pope, and B. W. Goad. 1973. Post- 
glacial colonization of the Matamek River, Quebec, by 
fishes. Journal of the Fisheries Research Board of 
Canada 30: 1583-1589. 

Ricker, W. E. 1975. Computation and interpretation of 
biological statistics of fish populations. Bulletin of the 
Fisheries Research Board of Canada 191. 382 pp. 

Rimmer, D. M. 1975. Rearing Atlantic Salmon (Salmo 
salar L.) in fishless lakes of the Matamek River 



system, Quebec. M.Sc. thesis. University of Waterloo, 

Waterloo, Ontario. 204 pp. 
Schiefer, K. L. 1969. Ecology of Atlantic Salmon, Salmo 

salar L., in the Matamek River system. M.Sc. thesis, 

University of Waterloo, Waterloo, Ontario. 63 pp. 
Sinha, V. R. P. and H. Evans. 1969. Salmon rearing in 

mountain tarns. The scales and growth of fish in 

Llynau Dyrnogydd, Teyrn and Cilan. Journal of Fish 

Biology 1: 285-294. 

Received 17 June 1977 
Accepted 11 October 1977 



Species-area Relationships for Vascular Plants of 
Some St. Lawrence River Islands 



J. McNeill and W. J. Cody 

Biosystematics Research Institute, Agriculture Canada, Ottawa KIA 0C6 

McNeill, J. and W. J. Cody. 1978. Species-area relationships for vascular plants of some St. Lawrence River islands. 
Canadian Field-Naturalist 92( 1): 10-18. 

A detailed survey has been made of the vascular plant species on each of the 17 islands and one mainland area of the St. 
Lawrence Islands National Park, Ontario. In a comparison with the area of each island the number of species was found to 
give a close and almost equally good fit to both the semi-log and the power function models, as well as to a curvilinear 
modification of the former. Gordon Island, which differs from the others in its sandstone substrate, is somewhat richer in 
species than predicted by the semi-log regression. A comparison with similar data from limestone islands in Lake Ontario 
suggests that the latter may show greater species diversity, but a significant difference is not established. From the power 
function fit, the St. Lawrence River islands appear floristically as segments of a continental area with isolation playing little or 
no part in determining species composition. This is discussed in terms of extinction/ immigration theories of island 
biogeography. 

Key Words: island biogeography, species diversity, St. Lawrence Islands National Park, Ontario. 



As part of a phytogeographic study of the St. 
Lawrence Islands National Park, Ontario, a 
detailed survey of the vascular plant species 
composition of the 17 islands and the one 
mainland area of the park (Figure 1) was 
completed in 1975 by Cody (Report to Parks 
Canada by W. J. Cody 1976). This was an 
extension of earlier studies conducted by staff 
and students of the Biology Department, 



Queen's University, Kingston between 1966 and 
1974 (Reports to Parks Canada by R. E. Beschel 
1970; A. Crowder and A. E. Garwood 1971; 
J. W. Johnson 1974), and, prior to 1966, by 
W. G. Dore of the Plant Research Institute, 
Canada Department of Agriculture. The species 
occurrence data obtained (Table 1) were 
analyzed in terms of models of relationship 
between the size of a particular area and the 



Table 1 — Area and number of vascular plant species recorded from the islands and mainland of the St. Lawrence 

Islands National Park 



Island 



Area (A) 
(ha) 



\OgeA 



Number of 
species (S) 



logc5 



1. Adelaide 

2. Aubrey 

3. Beaurivage 

4. Camelot 

5. Cedar 

6. Constance 

7. Endymion 

8. Georgina 

9. Gordon 

10. Grenadier* 

11. Mallorytown 

12. McDonald 

13. Mermaid 

14. Milton 

15. Mulcaster 

16. Squaw 

17. Stovin 

18. Thwartway 



5.30 


1.6681 


251 


5.5255 


5.79 


1.7556 


197 


5.2832 


4.38 


1.4777 


218 


5.3845 


9.47 


2.2481 


221 


5.3982 


9.31 


2.2309 


256 


5.5452 


2.95 


1.0832 


161 


5.0778 


4.41 


1.4841 


208 


5.3376 


9.43 


2.2439 


249 


5.5175 


6.27 


1.8363 


280 


5.6348 


437.82 


6.1613 


500 


6.2146 


38.04 


3.6386 


288 


5.6630 


14.17 


2.6506 


269 


5.5946 


1.54 


0.4305 


116 


4.7536 


3.24 


1.1750 


199 


5.2933 


5.38 


1.6833 


246 


5.5054 


3.05 


1.1154 


210 


5.3471 


4.13 


1.4178 


180 


5.1930 


36.45 


3.5960 


289 


5.6665 



*Data on area and species refer to the entire island, although only a portion of the island is in the national park. 



10 



1978 



McNeill and Cody: Species Diversity, St. Lawrence Islands 



11 



CORNWALL, 



• PETERBOROUGH 




ST. LAWRENCE RIVER ISLANDS 



1 ADELAIDE 


10 GRENADIER 


2 AUBREY 


11 MALLORYTOWN 


3 BEAURIVAGE 


12 McDonald 


4 CAMELOT 


13 mermaid 


5 CEDAR 


14 MILTON 


6 CONSTANCE 


15 MULCASTER 


7 ENDYMION 


16 SQUAW 


8 GEORGINA 


17 STOVIN 


9 GORDON 


18 THWARTWAY 



Figure 1. Map of the upper portion of the St. Lawrence River showing the positions of the areas whose species 
composition was studied. The inset map shows the position in relation to Lake Ontario and to the Lake Ontario 
islands studied by Hainauh (1968). The numbers are those given to the islands in Table I. 



number of species occurring within it. This was 
done in order to explore a number of questions 
regarding the ecology and biogeography of these 
islands, both as a group and in relation to other 
studies of island biogeography (MacArthur and 
Wilson 1967; Simberloff 1974). 

There are five main questions. (1) Do the 
species-area relationships suggest that the 
islands form a homogeneous group or are any 
significantly different from the others? (2) Which 
of the possible models of species-area relation- 
ship shows the best fit to the data? (3) What 
conclusions regarding the ecology and floristic 
richness of the islands are suggested by fitting 
these models? (4) Do any differences emerge in 
comparisons with species-area relationships 
among the nearby Lake Ontario islands with a 



basically similar flora but on a limestone rather 
than granitic substrate? (5) Does the mainland 
area in the survey show any differences from the 
islands that might be interpretable in terms of 
island biogeographic theory? 

Most data on the occurrence of animal species 
are based on counts of the number of individuals 
of each taxon present in a given area; such 
information cannot usually be obtained, how- 
ever, for plants. Instead, in order to use models 
of species distribution such as the logarithmic 
series (Fisher et al. 1943) or the log-normal 
(Preston 1962), it is necessary to assume that the 
number of "individual plants" occupying a given 
area is proportional to that area. This is 
plausible only if the areas concerned are all 
within the same ecological association, or 



12 



The Canadian Field-Naturalist 



Vol. 92 



comprise similar sets of associations. The St. 
Lawrence River islands probably satisfy the 
second condition although the amount of 
logging, farming, and other human interference 
has varied from island to island. 

Species-area Models 

Two main models were tested. The first is 
based on the assumption that the logarithmic 
series expresses the frequency curve of the 
number of species containing increasing num- 
bers of individuals (Williams 1964, Chapter 4). It 
has been found empirically that if the number of 
plant species in a single homogeneous associa- 
tion is counted in a series of samples (e.g., 
quadrats), then (except for very small areas) the 
number of species recorded usually increases 
linearly as the logarithm of the area sampled 
(usually expressed as the logarithm of the 
number of quadrats). The slope of the straight 
line best fitting the plot of number of species (5) 
against log area is a measure of the diversity of 
the particular association. The equation of the 
straight hne can be expressed as S= a\n A + D, 
where a is the Index of Diversity, A the area (or 
number of equal-sized quadrats), and D a 
constant that depends on factors such as the 
plant density of the particular association and 
the thoroughness with which the number of 
species has been recorded. Kobayashi (1975) has 
modified this model so that the relationship, 
although no longer entirely linear, applies even 
to very small areas. The modified model takes the 
form 5* = a' In (l+A/E) where £" is a 
constant that Kobayashi calls the elemental area 
of the particular association; this should not be 
confused with the minimal area of some phyto- 
sociologists (a questionable concept (see Good- 
all 1970)) but is related to the characteristic area 
(C) of an association, as developed by Ko- 
bayashi (1974), in that C = {e + \) E. 

The second model has generally been found 
more apphcable to large areas with a diversity of 
associations and environments (Williams 1964, 
Chapter 5; MacArthur and Wilson 1967, 
Chapter 2). Here the number of species {S) of 
any one group of organisms may be related to 
the area (^4) according to the equation 5" - CA^, 
which can be expressed as log S = z log A + 
log C. Thus there is a linear relationship between 
the logarithm of the number of species and the 
logarithm of the area. This relationship has been 



applied extensively to island biogeography and 
the values of z determined empirically are 
reasonably consistent with the theoretical value 
of 0.27, calculated under the assumption that the 
frequency curve of species containing various 
numbers of individuals is log-normal (Preston 
1962). Where the areas being studied are samples 
of increasing size from the same island or from a 
continental region, values of the constant z are 
usually much lower: 0.12-0.17 as against the 
common range of 0.20-0.34. The constant C, 
like D (above), is a function of population 
density and varies widely with the type of 
organisms involved and the biogeographic 
region of the world. 

Species! Log Area Model 

Although each of the St. Lawrence River 
islands comprises more than one ecological 
association they are sufficiently small and 
topographically uniform for it to be worth 
applying the first model to them. Figure 2 shows 
the number of species recorded from each (up to 
1975) plotted against the natural logarithm of 
the area of each island; it also shows the fitted 
regression line (F= 57.0 X+ 121.0; where Y- S 
and X - log A) and the 95% prediction limits 
(Sokal and Rohlf 1969) about that Une. The 
coefficient of determination (r^) is 0.88 and the 
standard deviation about the fitted line {Syx) is 
28.47; these values represent a particularly good 
fit. For example, although Diamond and Mayr 
(1976) quote an r^ = 0.98 for bird species data 
from the Solomon Islands, this refers only to the 
"nonisolated" islands. The value for all 50 
islands is r^ - 0.85; with ^ - 39.4, their 5^^^ - 9.09 
gives a coefficient of variation (F) of 23.1 as 
against 11.8 for this St. Lawrence River islands 
fit. The corresponding figures for the plant 
species data of Johnson et al. (1968) from the 
California coast islands are r- - 0.60 and 
V = 58.3 (5, , = 122.5 with S = 210). 

For the St. Lawrence islands data all points 
fall within the 95% prediction limits of the 
regression {S= 183 to 299 at In J =2.1053). 
Gordon Island, however, does not fit the Hnear 
relationship postulated as well as do the others. 
This suggests that the assumption of ecological 
homogeneity may not be valid for it and indeed 
Gordon, an island with low relief, is the only one 
with a sandstone substrate, all the others being 
granitic. If Gordon is excluded from the analysis 



1978 



McNeill and Cody: Species Diversity, St. Lawrence Islands 



13 





500 - 






/ 10* / / 




450 - 






'/ ■' 




400 - 








Q 

Q 

tr. 
o 


350 - 




/ 
/ 

/ 




o 

UJ 

cc 
CO 


300 - 




/ 
/ 
A9 


/ 18 / 


UJ 

o 






/ 
/ 5 / 


/il2 /^ 


u. 
O 

d 

2 


250 - 






/ 
/ 

/ 
/ 
/ 






/ 


• 3/ 4 


/ 






/ 


16« ?•/ 


/ 




200 - 


/ 
/ 
/ 


14»/ .2 // 








/ 


/.17 / 
• 6 / 


MODEL 1 
S = 57.0 logj,A + 121.0 




150 - 


/ 

• 13 


/ 
/ 
/ 
/ 

/ 
/ 
/ 

/ 


r2 = 0.88 Syx = 28.47 




100 - 


/ 
/ 
/ 
/ 








75 - 


/ 










1 1 


1 1 1 1 1 1 



3.0 4.0 5.0 

LOG„ HECTARES (LOG„ A) 



Figure 2. Number of species (5^ plotted against the natural logarithm of the area (log^/l) for the St. Lawrence River 
islands. Regression line of S upon \o%eA is fitted; broken lines indicate the 95% prediction limits of species number 
based on the regression equation. The numbers are those given to the islands in Table 1. 



the position and slope of the regression line 
{y = 57. 5x +116.7) are little changed, but it 
provides a rather better fit (r2 = 0.91; ^y.x - 
25.63). Because the probability upon which 
prediction limits are based is that of an 
additional observation belonging to the set for 
which the regression has been calculated, it is 
legitimate to compare the number of species on 
Gordon Island with the prediction limits of the 
new regression for an island of that size. The 95% 
prediction is for 166 to 279 species whereas 280 
species are recorded from Gordon. On the other 
hand, the mainland area round Mallorytown 
Landing, and Thwartway, the least disturbed 
island, are both somewhat species-poor. Even 



when removed from the analysis, however, they 
remain within the 95% prediction limits based on 
the regression line of the other islands. 

By treating the sandstone substrate of Gordon 
Island as an 'effect' in a hierarchical analysis of 
variance, the significance of the resultant 
increase in the variance accommodated by the 
regression was explored. The F value obtained 
(2.70 for 1 and 15 degrees of freedom) is not, 
however, significant at the 10% level. 

The index of diversity (a) for the apparently 
homogeneous group of 17 areas with a granitic 
substrate is 57.5 with 95% confidence limits of 
47.3 to 67.7. Although indices calculated for 
single associations in arid land in New South 



14 



The Canadian Field-Naturalist 



Vol. 92 



Table 2 — Area and number of vascular plant species recorded from islands and land areas in eastern Lake Ontario 

(data from Hainault op. cit.) 



Island 



Area {A) 
(ha) 



\0geA 



Number of 
species {S) 



loge5 



19. Long Point 

20. Timber 

21. Swetman 

22. Main Duck 

23. Yorkshire 

24. Galloo 

25. Little Galloo 

26. Calf 

27. Stony 

28. Stony Point 



055.5 


6.9618 


467 


6.1463 


46.2 


3.8330 


221 


5.3982 


35.0 


3.5554 


156 


5.0499 


208.0 


5.3375 


377 


5.9323 


20.6 


3.0253 


201 


5.3033 


809.8 


6.6968 


360 


5.8861 


19.5 


2.9704 


73 


4.2905 


15.6 


2.7473 


132 


4.8828 


566.4 


6.3393 


368 


5.9081 


700.5 


7.4413 


450 


6.1093 



Wales range from 4.8 to 6.2 and in alpine valleys 
in Switzerland from 3.4 to 12.1 (see Williams 
1964), those reported by Curtis (1959, p. 517) for 
forest communities of Wisconsin are very similar 
to those found in this study and range from 40. 1 
to 70.4. Although partly a reflection of real 
difference in species diversity (e.g., in the higher 
alpine habitats in Switzerland), the discrep- 
ancies in the index values are largely due to the 
islands and the Wisconsin forest communities 
comprising several associations. The highest 
reported index of diversity for plant species is 
114.2 from a Malaysian rain forest community 
(Poore 1968; Lamont et al. 1977). 

Species! Log Area Model (Kobayashi 
Modification) 

Kobayashi's (1975) modification of the 
species/ log area model can readily be fitted by 
an iterative procedure using the value of a 
already calculated as a first approximation of a' 
and e-^'" as that of E\ the formula of the result- 
ant best fit to the 17 areas with granitic substrate is 
>S=58.2 1n(l +/4/0.1415); this was confirmed 
by a least-squares non-linear regression (Hartley 
1961). This formulation has the merit of the 
regression passing through the origin (no species 
at zero area) and is almost as good a fit as the 
other {^Y.x — 25.67). The characteristic area, 
which Kobayashi (1974) interprets as the unit 
size of sampling, is about 0.24 ha. 

Using the Kobayashi model, it is possible to 
compare the St. Lawrence River islands with 
eight islands and two adjacent land areas in 
eastern Lake Ontario for which data were 
gathered by Hainault (1968) (see Table 2). At 
their closest, the Lake Ontario islands are only 
some 30 km to the south-west, but they are on a 



limestone substrate. The absolute numbers of 
species recorded by Hainault are much lower per 
unit area than those for the St. Lawrence islands, 
but these data are not directly comparable 
because Hainault's survey was carried out in a 
single season with only one or a few days on the 
smaller islands. 

Assuming that the relative thoroughness of 
Hainault's survey was about the same for each of 
his islands, the slope of a Kobayashi fit to these 
data can be compared with that obtained for the 
St. Lawrence islands (Figure 3). The best fit for 
the Lake Ontario data is when S = 73.9 
In (1 + ^/3.182); the deviation associated with 
this fit {Syx — 47.26) is much greater than that for 
the St. Lawrence islands. This does not seem to 
be exphcable by any features of the islands and 
land areas themselves, but rather reflects the 
incompleteness of the survey. For example the 
characteristic area is 5.5 ha, greater than the 
size of many of the St. Lawrence islands. 

The higher index of diversity of the Lake 
Ontario islands (73.9 against 58.2) appears to 
agree with the common experience that, under 
cool temperate conditions, Umestone habitats 
show greater diversity of species than do those 
on acid soils. An analysis of variance, however, 
shows that, when account is taken of the 
differences in the relative positions of the two 
curves (the E values), the additional variance 
accommodated by separate indices of diversity is 
not significant at the 10% level (F-value 2.46 for 
1 and 23 degrees of freedom). The available data 
are, therefore, inadequate to justify the sug- 
gestion that the Lake Ontario islands are 
floristically more diverse; more intensive ex- 



1978 



McNeill and Cody: Species Diversity, St. Lawrence Islands 



15 



500 - 










• 10 / 

/ 019 


/ 


450 - 










/ / 


28 


400 - 










' 22 / 
/27 




350 - 




S=58.2log^ (1 + A/0.1415) 
SY.x = 25.7 




/ 


/ ° 024 




300 - 






^2 


8»«11 






250 - 




• 1 *V^ 

S 8*/ 
•l5 7 

• 3/ '4 




20/ 
V 






200 - 




14 •/ ,2 


23 


/ 






150 - 




/ "IS / 


26 


21 






100 - 


c./ 


\. X CA / 


25 




S = 73.9log^(1 + A/3.182) 
SY.x = 47.3 




50 - 


/ 












- 


















1 1 1 1 


1 


1 


1 1 1 


1 



LOG. HECTARES (LOG. A) 



Figure 3. Number of species {S) plotted against the natural logarithm of the area (loge/4) for the St. Lawrence River (•). 
and Lake Ontario (o) islands. Least squares regression equation S- a log (I - A/E) are fitted for the two sets of 
islands. The characteristic areas indicated by the two regressions are marked (CA). The numbers are those given 
to the islands in Tables 1 and 2. 



ploration of these islands is needed to confirm or 
reject this. The single index of diversity for the 
two sets of islands combined is 66.0. 

Power Function Model 

Applying the second model to the St. 
Lawrence River islands (Figure 4), the non- 
linear power function regression explains almost 
as much of the variance in species number as 
does the linear semi-log regression (Syx = 28.3). 
Gordon Island again appears unusually species- 
rich, but in this plot Mermaid Island (number 
13) is identified as being markedly species-poor. 
This appears to be a reflection of its absolute size 



being so small that the number of possible 
habitats is restricted to a greater extent than is 
predicted by its relative size (i.e., this model is 
not appHcable to such small areas as Mermaid 
Island). The least squares fit for all 18 areas is 
S = 158 y4''^. This is plotted by the upper curve 
in Figure 4, which suggests that Grenadier, the 
one very large island, may be dominating the 
regression. If this island is omitted, however, the 
resultant regression equation (S = 160 .4°'*) is 
almost identical to that calculated for all areas. 
The two regression curves are represented, on an 
expanded area scale, by the two lower curves in 
Figure 4. 



16 



The Canadian Field-Naturalist 



Vol. 92 




AREA IN HECTARES (A) 



Figure 4. Number of species {S) plotted against the area (A) for the St. Lawrence River islands. Least squares 
regression curves of the power function of A are fitted. The solid line curves are based on all 18 areas; the broken 
line is the regression curve with number 10, Grenadier Island, excluded. The upper and lower curves correspond 
to the upper and lower A scales marked on the abcissa. The numbers are those given to the islands in Table I. 



Discussion 

Exploring these species-area relationships has 
answered some questions and left others open to 
further study. 

The areas in the St. Lawrence Islands 
National Park in general form a homogeneous 
set of vascular plant associations. The one 
possible exception is Gordon Island, which is 
somewhat richer in number of species than 
would be predicted by its size. Our surveys were 
in no way biased towards species recording on 
Gordon Island and so it would be of particular 
interest to see whether this characteristic is borne 
out by data from other groups of organisms. 

Williams (1964) concluded empirically that 
the power function model (model 2) rarely 
applied in areas below about 1 km^ while the 
semi-log model (i.e., species/ log area) was the 
most appropriate for single associations ranging 
from a few square metres to hundreds of square 
kilometres. Kilburn (1966) has questioned this 
on the basis of observations on prairie and forest 
plots in Illinois and Wisconsin and of a re- 
examination of Hopkins' (1955) data from 
various communities in Britain. Both Hopkins' 
and Kilburn's data combined species numbers 



for vascular plants with those for various groups 
of non-vascular plants. By disentangling the 
species numbers in each taxonomic group (albeit 
speculatively) Kobayashi (1975) succeeded in 
obtaining a closer fit for these data to his 
modification of the semi-log model than that 
obtained by Hopkins (semi-log) or Kilburn 
(power function). The St. Lawrence islands data 
cannot be adduced as evidence in favor of one of 
these possibilities over the others as they fit all 
three almost equally well. This is not altogether 
unexpected. The islands comprise more than the 
single association specified for the strict applica- 
tion of the semi-log model, yet they are not as 
diverse as the larger islands to which the power 
function model regularly applies. Moreover, the 
data are confined to one group of organisms. 

The concept of species diversity as a function 
of the slope of the species / log area regression (a) 
rather than the absolute number of species 
recorded requires comment. Whittaker (1972) 
and Peet (1974) discuss concepts of diversity 
pointing out the practical problems of develop- 
ing a direct measure of species number per unit 
area that will be comparable from one study to 
another. Slope measures are comparable but 



1978 



McNeill and Cody: Species Diversity, St. Lawrence Islands 



17 



their interpretation in terms of species diversity 
depends to some extent on the model being used. 
For a species/ log area curve obtained from 
successively greater areas of the same associa- 
tion, the slope is a measure of relative species 
diversity ('richness' in Peet's (1974) terminology) 
in that the mean number of individuals per 
species must be lower with a steep slope than 
with a gentle one, i.e., the Ukehhood of any two 
plants within a given area being of a different 
species is greater. 

The index of diversity calculated from the 
semi-log model for the St. Lawrence River 
islands gave 95% confidence limits of 47-68. The 
similarity with the values calculated from forest 
stands in Wisconsin suggests that the floristic 
diversity of the islands is comparable with that of 
other similar areas, and that they are neither 
notably species-rich nor notably species-poor. 
The suggestion that the Lake Ontario islands 
with a limestone substrate may have greater 
species diversity could not be confirmed with the 
available data; more extensive collecting on that 
group of islands is required. 

Most zoogeographic studies of islands seek to 
interpret species numbers in terms of equiUbria 
between rates of extinction and immigration 
(Simberloff 1974). The applicability of the 
concept of regular extinction and recoloniza- 
tion in ecological time is difficult to conceive for 
most perennial vascular plants, whether trees or 
herbs. Many such "individuals" may have a life 
span of hundreds if not thousands of years (see, 
for example, Harberd 1961, 1962, 1967) and 
extinction is more plausibly a function of the 
destruction of particular habitats than one 
directly related to species density. In such cases, 
recolonization is likely only if the habitat is in 
some way re-established. There are, of course, 
vascular plant species, mostly annual, for which 
the extinction-colonization pattern is the rule, 
but in the St. Lawrence islands such species 
make up little more than 10% of the total flora. 

Although there are notable exceptions, such 
as the experimental work on mangrove islands 
by Simberloff and Wilson (Simberloff 1 976a, b), 
many zoological studies appear to equate 
extinction with the failure to record a species in a 
particular survey. The ease with which even 
experienced collectors, searching appropriate 
habitats, can overlook an immobile vascular 



plant species makes this seem a highly ques- 
tionable assumption. Like many of the pub- 
lished botanical data on species presence (e.g., 
Johnson et al. 1968; Johnson and Raven 1973), 
our data represent observations accumulated 
over several years. Moreover, our data are 
unusually complete because the relatively small 
areas involved have been intensively studied by 
several workers over a number of years and all 
the voucher specimens have been available to us. 
Nevertheless, the rate of accumulation of 
records and further work since the completion of 
the second author's survey leads us to believe 
that the records for each island are only around 
95% complete. If extinction and recolonization 
are factors at all, they are likely to operate on the 
rarest species, the very ones that may be 
overlooked in even the most thorough surveys. 

The value of the constant z in the power 
function model is regarded as an indicator of 
relative rates under the extinction-immigration 
hypothesis (MacArthur and Wilson 1967). The 
value of z obtained from the St. Lawrence River 
islands is substantially and significantly lower 
(95% confidence limits of z: 0.1 6-0.22) than the 
theoretical value of 0.27 calculated under the 
assumption of a log-normal distribution of 
individuals. Such a departure is generally 
interpreted in terms of high immigration rates 
(Diamond and Mayr 1976). The value that we 
have found, however, is consistent with those 
obtained by taking samples of increasing size 
from the same island or from a continental area, 
a situation in which there would be an available 
pool of immigrants just outside the arbitrary 
area boundary. 

On this basis the islands can be looked upon 
floristically as segments of a continental area 
with isolation playing little or no part in 
determining species composition. This would be 
supported by the fact that Mallorytown, part of 
the mainland, fits the regression well and does 
not have more species than predicted for a 
corresponding insular area. Whether this is 
owing to the extinction-immigration hypothesis 
being inappUcable to vascular plant species is 
difficult to determine because of the proximity 
of all the St. Lawrence River islands to the 
mainland or to large islands not included in the 
survey. An alternative explanation of the z 
values being significantly less than 0.27 is that 



18 



The Canadian Field-Naturalist 



Vol. 92 



the frequency curve of individuals per species is 
not log-normal. 

Acknowledgments 

We are grateful to D. Munro for field 
assistance during the summer of 1975, to G. P. 
Bebee and M. J. McCauley for technical 
assistance, to A. Crowder for suggesting the 
comparison with the islands in eastern Lake 
Ontario, and to L. P. Lefkovitch and K. Price 
for advice and assistance in some of the 
statistical tests and for reviewing the manuscript. 

Literature Cited 

Curtis, J. T. 1959. The vegetation of Wisconsin. University 

of Wisconsin Press, Madison. 657 pp. 
Diamond, J. M. and E. Mayr. 1976. Species-area relation 

for birds of the Solomon Archipelago. Proceedings of the 

National Academy of Sciences, U.S.A. 73: 262-266. 
Fisher, R. A., A. S. Corbet, and C. B. Williams. 1943. 

The relation between the number of species and the 

number of individuals in a random sample of an animal 

population. Journal of Animal Ecology 12: 42 58. 
Goodall, D. W. 1970. Statistical plant ecology. Annual 

Review of Ecology and Systematics I: 99-124. 
Hainault, R. 1968. Flora of the islands of eastern Lake 

Ontario. M.Sc. thesis. Queen's University, Kingston, 

Ontario. 175 pp. 
Harberd, D. J. I96I. Observations on population structure 

and longevity of Festuca rubra L. New Phytologist 

60: 184-206. 
Harberd, D.J. 1962. Some observations on natural clones 

in Festuca ovina. New Phytologist 61: 85-100. 
Harberd, D. J. 1967. Observations on natural clones in 

Holcus mollis. New Phytologist 66: 401-408. 
Hartley, H. O. 1^961. The modified Gauss-Newton method 

for the fitting of non-linear regression functions by 

least squares. Technometrics 3: 269-280. 
Hopkins, B. 1955. The species-area relations of plant com- 
munities. Journal of Ecology 43: 409 426. 
Johnson, M. P., L. G. Mason, and P. H. Raven. 1968. 



Ecological parameters and plant species diversity. Ameri- 
can Naturalist 102: 297-306. 

Johnson, M. P. and P. H. Raven. 1973. Species number 
and endemism: the Galapagos Archipelago revisited. 
Science (Washington) 179: 893-895. 

Kilburn, P. D. 1966. Analysis of the species-area relation. 
Ecology 47: 831-843. 

Kobayashi, S. 1974. The species-area relation. I. A model 
for discrete sampling. Researches on Population Ecology 
15: 223-237. 

Kobayashi, S. 1975. The species-area relation. II. A second 
model for continuous sampling. Researches on Popula- 
tion Ecology 16: 265-280. 

Lamont, B. B., S. Downes, and J. E. D. Fox. 1977. 
Importance-value curves and diversity indices applied to 
a species-rich heathland in Western Australia. Nature 
(London) 265: 438-441. 

MacArthur, R. H. and E. O. Wilson. 1967. The theory of 
island biogeography. Princeton University Press, Prince- 
ton, New Jersey. 203 pp. 

Peet, R. K. 1974. The measurement of species diversity. 
Annual Review of Ecology and Systematics 5: 285-307. 

Poore, M. E. D. 1968. Studies in Malaysian rain forest. I. 
The forest on Triassic sediments in Jengka Forest 
Reserve. Journal of Ecology 56: 143-196. 

Preston, F. R. 1962. The canonical distribution of com- 
monness and rarity. Ecology 43: 185-215, 410-432. 

Simberloff, D. S. 1974. Equilibrium theory of island bio- 
geography and ecology. Annual Review of Ecology and 
Systematics 5: 161-182. 

Simberloff, D. S. 1976a. Experimental zoogeography of 
islands: effects of island size. Ecology 57: 629-648. 

Simberloff, D. S. 1976b. Species turnover and equilibrium 
island biogeography. Science (Washington) 194: 572-578. 

Sokal, R. R. and F.J. Rohlf. 1969. Biometry. W. H. 
Freeman and Company, San Francisco. 776 pp. 

Whittaker, R. H. 1972. Evolution and measurement of 
species diversity. Taxon 21: 213-251. 

Williams, C. B. 1964. Patterns in the balance of nature. 
Academic Press, London and New York. 324 pp. 

Received 28 May 1976 
Accepted 2 October 1977 



Evaluation of the Winter Range of White-tailed 
Deer in Point Pelee National Park, Ontario 



John B. Theberge 



Faculty of Environmental Studies, University of Waterloo, Waterloo, Ontario N2L 3G1 

Theberge, John B. 1978. Evaluation of the winter range of White-tailed Deer in Point Pelee National Park, Ontario. 
Canadian Field-Naturalist 92(1): 19-23. 

The range of White-tailed Deer {Odocoileus virginianus) at Point Pelee was studied to determine whether previously reported 
overutilization was occurring. Plots (256, each 9.3 m^) were established throughout the 4.5-km2 deer range. Of the 31 most 
abundant species of woody plants (non-vine), 18 were browsed. Availability of browse species, measured as stems of woody 
plant species, correlated with use. On only three of the plots did browsing on any species exceed 33% of available stems. Vines 
supplemented other woody vegetation as deer browse, and observations of grazing in winter indicated some dependence on 
herbaceous food. Deer do not appear to be overutilizing any part of their range. 

Key Words: White-tailed Deer. Point Pelee, food of deer. 



According to Henry (1972, 1975), White- 
tailed Deer have been reportedly overutilizing 
their winter food supply over much of the deer 
range in Point Pelee National Park. Henry's 
conclusion was based on observations of 
movements and distribution of deer, not on any 
analysis of vegetation. I have tested this 
conclusion by analysis of browse availability and 
use, and present contrary findings. 

Past reports in Parks Canada files and the 
comments of wardens suggest that the deer herd 
has not exceeded approximately 25 animals for 
close to 25 years. In 1951, V. E. F. Solman 
(unpublished report. Parks Canada, Point Pelee 
National Park) estimated 25 deer, and com- 
mented that food was available to support more 
deer. In 1956, the herd was reduced by 12 
animals (D. Wigle. The deer on Point Pelee. 
Unpublished report. Parks Canada, Point Pelee 
National Park). In the winter of 1975-76, the 
herd consisted of 22 or 23 animals, based on 
repeated observations of marked and known 
deer over a period of 3 months (J. B. Theberge 
and S. M. Oosenbrug. Behaviour and popula- 
tion Hmitation of White-tailed Deer at Point 
Pelee. Unpublished report. Parks Canada, Corn- 
wall, Ontario). The density, approximately 
5.6 deer/ km2, is low compared with that of 
nearby Rondeau Peninsula recently with 
19 deer/km^ (D. Euler. 1974. An analysis of the 
recruitment potential of the White-tailed Deer 
population in Rondeau. Unpublished report. 
Ministry of Natural Resources, Toronto, On- 
tario. 3 pp.). The density of deer at Pelee is 
greater than a mean of 2.1 deer/km^ for areas 



within central Ontario (King 1976). 

In this study we set out to determine whether 
food availability was Umiting deer; the limi- 
tation would be indicated by overutilization of 
the winter food supply. 

Study Area 

The 15.0-km2 park is situated on a peninsula 
that juts out into Lake Erie, in Essex County, 
Ontario. Most of the park is marsh; the 4.5-km2 
deer habitat lies primarily west and south of the 
marsh. The deer habitat is isolated because of 
intensive agriculture and urbanization north of 
the peninsula. 

Point Pelee's forests are ecotonal between the 
Great Lakes-St. Lawrence, and deciduous 
forests (Rowe 1972). A variety of vegetative 
communities exist, all extensively modified by 
logging, livestock-grazing, and fishing prior to 
the establishment of the park in 1918, or 
agriculture and recreational use since then 
(Battin 1975). Approximately 120 ha are in 
early post-agriculture successional stages, with 
grasses (Gramineae) dominant in the youngest 
fields and dogwoods {Cornus spp.), sumac 
{Rhus spp.), and willow (Salix spp.) dominant in 
older fields. Approximately 41 ha are wet 
woodlands flooded periodically by high lake 
levels and dominated by silver maple (Acer 
saccharinum). On former sand dunes and beach 
ridges are 270 ha of a variety of shrub and 
tree communities. I subdivided those com- 
munities, as did Henry (1972, 1975) into 
"red cedar forest" and "cedar savanna," both late 
successional stages dominated by Juniperus 



19 



20 



The Canadian Field-Naturalist 



Vol. 92 



virginiana, and also "hackberry forests" con- 
sisting of large hackberry trees {Celtis oc- 
cidentalis) and oak (Quercus spp.) with a red 
cedar understory in places. Maycock (1971. An 
ecological study of the forests of Point Pelee, 
Essex County, Ontario. Unpublished report, 
Parks Canada, Point Pelee National Park) 
identified and mapped this vegetation in detail. 

Methods 

Field data were collected between 1 May and 
30 September 1974, with some additional 
observations of feeding deer made incidentally 
to deer behavioural research between 15 January 
and 15 April 1975. 

Transects (32) were established throughout 
the park, exclusive of marsh, in the five deer 
habitats. The percentage of the total deer range 
represented by each habitat, and number of 
transects in each were as follows: hackberry 
forest (47%), 15 transects; abandoned farmland 
(30%), 7; wet forest (10%), 5; red cedar forest 
(8%), 3; cedar savanna (5%), 2. These pro- 
portions were chosen primarily to reflect relative 
sizes of these habitats, but also to represent, with 
single transects in each, the more detailed 29 
vegetative zones identified and mapped by 
Maycock (op. cit.). The size of the abandoned 
farmland was greater by 12% than the com- 
parable area described by Henry (1972, 1975); 
wet forest was smaller by 8%. These differences 
were due to my inclusion of two additional small 
habitats described by Henry, shrub and her- 
baceous strand, into the five habitats, because I 
considered them too small for accurate separate 
analysis. Also the higher levels of Lake Erie may 
have added to wet woodland in 1972 when 
Henry conducted his study. The sizes of the areas 
were determined by planimetry on aerial 
photographs, and ground checks. 

Within vegetative zones, each transect was 
located by subjectively finding a representative 
area and then randomly selecting a compass 
bearing for the transect. Each transect consisted 
of eight plots, 7.6 X 1.2 m, located consecutively 
along a stretched tape. Data collected for each 
plot included these: relative percentage cover of 
woody, herbaceous, and vine growth within 2 m 
of the ground; the ranked five most abundant 
species of woody, herbaceous, and vine growth; 
the percentage of stems of each species browsed 



(a "stem" was defined as single growth arising 
from the ground). The last named measure was 
simplified in analysis to whether or not a species 
was browsed in a plot, since browsing was 
always light (on only three plots exceeding 33% 
of stems). 

The data were analyzed to determine avail- 
ability and extent of utilization of browse 
species. Use of each species of woody vegetation 
was determined by adding the number of plots 
on which the species was browsed. Utilization so 
measured reflected relative amounts of various 
species eaten by deer to the extent that the 
location of transects reflected fairly the pro- 
portional availability of browse species. The 
proportion of transects in each habitat was 
carefully chosen to represent accurately the total 
deer habitat, as described. 

Availability of browse species was determined 
by calculating prominence values for each 
species. This is an index of "commonness," 
obtained by multiplying the sum of densities of a 
species on all plots by the square root of its 
percent frequency of occurrence on plots. 
Density values for each plot were scored 5 for the 
most abundant species, 4, 3, 2, 1 for the others 
with decreasing degrees of abundance. Prom- 
inence values were used to describe availability 
of food species because they take into account 
both density and distribution and as such were 
viewed as more accurately reflecting availability 
to a wandering feeder such as deer than either 
measure by itself. Prominence values have been 
commonly used as a descriptive and analytical 
measure by botanists (Stringer and La Roi 1970; 
Douglas 1972), after first being applied to birds 
by Beals (1960). 

The availability of herbaceous vegetation and 
vines was determined (Theberge. 1975. Summer 
assessment of aspects of the ecology of White- 
tailed Deer in Point Pelee National Park. 
Unpublished report. Parks Canada, Cornwall, 
Ontario) but will not be described in detail here 
because utilization of those food items was 
determined only in general descriptive terms. 

Results and Discussion 

Eighteen (58%) of a total of 31 species (or in 
some cases genera) of woody plants (except 
vines) found on plots were browsed by deer 
(Table 1). Gooseberry (Ribes spp.) and hack- 



1978 



Theberge: White-tailed Deer, Point Pelee, Ontario 



21 



Table 1 — Availability and utilization of woody plants (non-vine) by White-tailed Deer at Point Pelee National Park, 1974 



Species 



Ava 


liability 




Utilization, 


Number of plots 


Total prominence 


number (%) 


where found 




value' 


of plots 


90 




2740 


55(61) 


74 




2585 


55(74) 


73 




2340 


36(49) 


49 




1542 


18(37) 


37 




807 


16(43) 


29 




789 


19(66) 


16 




339 


9(56) 


12 




214 


6(50) 


7 




156 


1(14) 


5 




152 


5(100) 


2 




134 




7 




117 


5(71) 


5 




115 


2(40) 


4 




95 


3(75) 


— 




79 

72 




6 




71 


2(33) 


— 




68 




5 




64 


1(20) 


— 




56 




— 




50 




— 




49 

48 




— 




36 




3 




29 
18 


3 


— 




18 




1 




18 


1 


— 




14 




1 




14 


I 


— 




11 





Hackberry {Celtis occidentalis) 

Gooseberry (Ribes spp.) 

Cherry {Prunus spp.) 

Dogwood (Cornus spp.) 

Raspberry {Rubus spp.) 

Staghorn sumac {Rhus typhina) 

Red cedar {Juniperus virginiana) 

Hop tree {Ptelea trifoliata) 

Sugar maple {Acer saccharum) 

Apple {Pyrus malus) 

White pine {Pinus strobus) 

Fragrant sumac {Rhus aromaticd) 

Rose {Rosa spp.) 

Silver maple {Acer saccharinum) 

Basswood {Tilia americana) 

Ash {Fraxinus spp.) 

Oak {Quercus spp.) 

Black walnut {Juglans nigra) 

Elderberry {Sambucus pubens) 

Hop hornbeam {Ostrya virginiana) 

Black locust {Robinia pseudo-acacia) 

Willow {Salix spp.) 

Tree of heaven {Ailanthus ahissima) 

Slippery elm ( Ulmus rubra) 

Mulberry {Morus rubra) 

Buttonbush {Cephalanthus occidentalis) 

Ground juniper {Juniperus communis) 

Lilac {Syringa sp.) 

Eastern Cottonwood {Populus deltoides) 

Redbud {Cercis canadensis) 

Sassafras {Sassafras albidum) 



'See text for method of calculating prominence values. 
^Omitted, as not browsed. 

berry were the most heavily used, on the basis ot 
total number of plots browsed, followed by 
cherry (Prunus spp.), staghorn sumac (Rhus 
typhina), dogwood (Cornus spp.), raspberry 
(Rubus spp.), and red cedar. 

The hackberry forest supported the most 
browsing by deer, totalling 133 (57%) tallies of 
plant species browsed on plots (Table 2). Wet 
forest, abandoned farmland, and red cedar 
forest ranked closely in that order, with cedar 
savanna supporting the least (Table 2). This 
order of browsing within habitats largely 
reflected differences in number of plots, which in 
turn reflected relative sizes of habitats (hack- 
berry was the largest and was most browsed, 
while cedar savanna was the smallest and least 
browsed). Disproportionately heavy browsing 
also occurred, however, as determined by 



examining the total amount of browsing per plot 
in each habitat (dividing total browsing, shown 
in Table 2, by the number of plots, shown in the 
footnote to Table 2, for each habitat). Hack- 
berry forest ranked highest in disproportionate- 
ly heavy use (value of 1 . 1 ), followed by red cedar 
forest (1.08), and wet forest (0.9). The other 
habitats ranked much lower: abandoned farm- 
land, 0.57, and cedar savanna, 0.31. 

On examining the relative availabihty of 
woody plants, hackberry ranked first in prom- 
inence value, followed in order by gooseberry, 
cherry, dogwood, raspberry, and staghorn 
sumac (Table 1). Availability and utilization of 
browse species by deer correlated with a high 
level of confidence (/ = 0.01) as determined by 
calculation of the correlation coefficient 
(r = 0.97). Only the species browsed by deer were 



22 



The Canadian Field-Naturalist 



Vol. 92 



Table 2 — Plots browsed by White-tailed Deer in various habitats at Point Pelee National Park, 1974 









Habitat 








Hackberry 


Red cedar 


Cedar 


Abandoned 




Species' 


forest^ 


forest 


savanna 


farmland 


Wet forest 


Hackberry 


38(69)3 


2(4) 




4(7) 


11(20) 


Gooseberry 


42(76) 


2(4) 




3(6) 


8(15) 


Cherry 


29(81) 


1(3) 




2(6) 


4(11) 


Staghorn sumac 


2(11) 


8(42) 


1(5) 


8(42) 




Dogwood 


1(6) 


4(22) 


3(17) 


2(11) 


8(44) 


Raspberry 


8(50) 


3(19) 




4(25) 


1(6) 


Red cedar 


2(22) 


2(22) 


1(11) 


4(44) 




Hop tree 


6(100) 










Fragrant sumac 


1(20) 


4(80) 








Apple 








5(100) 




Silver maple 










2(100) 


Rose 










2(100) 


Oak 


2(100) 










Sugar maple 


1(100) 










Elderberry 


1(100) 










Total (percent 












total browsing) 


133(57) 


26(11) 


5(2) 


32(14) 


36(15) 



'No species is listed that occurred on less than four plots. 

-Total number of plots was 256, with 120 in hackberry forest, 24 in red cedar forest, 16 in cedar savanna, 56 in abandoned 

farmland, and 40 in wet forest. 
^Number of plots where the plant species was browsed, followed in brackets by percentage of total plots in which the species 

occurred and was browsed. 



used in this calculation. 

Availability, measured by prominence value 
for stems of each species, does not take into 
account differences in life forms of various 
species, and hence cannot be considered com- 
pletely accurate. Nevertheless, the correlation of 
availability with use indicates that deer were 
feeding on the most abundant woody species in 
the park. 

Henry (1975) stated that "The hackberry and 
wet forest habitat types were also avoided 
because food plants were scarce and cover 
inadequate, especially in winter." My results are 
contradictory to those findings. Hackberry and 
wet forest habitats received the most plots 
browsed and browsing per plot. Henry observed 
deer relatively infrequently in those two habi- 
tats compared with the more open red cedar 
forest and abandoned farmland. His statement 
on lack of food plants was speculative and not 
backed up by an evaluation of browsing. His 
assertion of relatively low use of the two habitats 
is either valid in that it represented presence of 
deer but not necessarily feeding, or was biased by 
disproportionate probability in seeing deer in 
different habitats, a possibiUty he did not 



discuss, but from my experiences in the park, 
one that seems probable. 

Some species were browsed commonly when 
found by deer (apple 100%, silver maple 75%, 
gooseberry 75%) (Table 1). Although this may 
indicate a significant impact of browsing on 
these species, such is not the case, since even on 
these plots, browsing did not exceed 15% of 
available stems of these species. 

Observations were made of deer browsing on 
vines during this study. Wild potato vine 
{Impomoea pandurata) was seen being utilized 
in 30 observations. It is an uncommon vine, 
found only on 5% of plots. Wild grape {Vitis 
riparia) was seen being utilized 17 times. It, 
along with the less frequently used Virginia 
creeper {Parthenocissus quinquefolia) were the 
most common vines, found on 23 and 24% of 
plots respectively. In places, wild grape was 
abundant growing over red cedar and other low 
trees. 

Feeding observations made between 15 Jan- 
uary and 15 April 1975 showed that herbaceous 
plants were important as deer food. Twenty-four 
of 34 feeding observations were of grazing rather 
than browsing deer, and five of both grazing and 



1978 



Theberge: White-tailed Deer, Point Pelee, Ontario 



23 



browsing. Grasses were used most often, then 
tall scouring rush {Equisetum hyemale). The 
former is common in the park (on 47% of plots 
established throughout the park as described 
under Methods), the latter is locally abundant in 
wet woodlands and marsh borders. 

In summary, the results of this study show 
that, contrary to Henry's (1975) conclusions, 
which were based on distribution of deer in 
winter and not on vegetational analysis, there 
was no shortage of deer food in any habitats, and 
especially in hackberry and wet forests where 
most browsing occurred. Overutilization of the 
range was not occurring. Although Henry's 
statement is obviously ultimately true that 
"management of deer within the park would 
require the protection of habitat types affording 
both preferred forage and cover and sites with 
good cover and adjacent forage," food is not 
now limiting deer numbers. The vegetation 
could support more deer than at present. 
Supporting this statement are these facts: (1) 
browsing was spread over 18 species, (2) on only 
three plots did browsing exceed 33% of any 
species, (3) the seven most heavily used plant 
species were also the most common in the park, 
and one or another was a dominant species in 
each of the habitat types, (4) the whole range was 
available to deer in winter because of normally 
light or no snow cover, and (5) herbaceous 
vegetation supplements woody vegetation. 

Acknowledgments 

This study was made possible by a contract 



from Parks Canada administered by Bernie Lieff 
then at Cornwall, Ontario. Field data were 
collected primarily by summer assistants Susan 
Heffernan and Andrew Gordon. Help was 
extended by Superintendants Frank Camp and 
Don Harris and park wardens and interpreters 
who kept notes of incidental observations of 
deer. Fred Gilbert and Dave Euler provided 
initial comments on the manuscript. To all these 
people I express my thanks. 

Literature Cited 

Battin, J. 1975. Land use history and landscape change, 

Point Pelee National Park, Ontario. M.A. thesis, 

University of Western Ontario, London. 384 pp. 
Beals, E. I960. Forest bird communities in the Apostle 

Islands of Wisconsin. Wilson Bulletin 72(2): 156-181. 
Douglas, G. W. 1972. Subalpine plant communities in the 

western North Cascades, Washington. Arctic and Alpine 

Research 4(2): 147-166. 
Henry, B. A. M. 1972. The ecology of the White-tailed 

Deer in Point Pelee National Park. M.Sc. thesis. 

University of Western Ontario, London. Ill pp. 
Henry, B.A.M. 1975. Habitat use and home range of 

White-tailed Deer in Point Pelee National Park, Ontario. 

Canadian Field-Naturalist 89(2): 179-181. 
King, D. R. 1976. Estimates of the White-tailed Deer 

population and mortality in central Ontario, 1970-1972. 

Canadian Field-Naturalist 90(1): 29-36. 
Rowe, J. S. 1972. Forest regions of Canada. Revised 

edition. Canadian Forestry Service Publication Number 

1300. 172 pp. 
Stringer, P. W. and G. H. La Roi. 1970. The Douglas Fir 

forests of Banff and Jasper National Parks, Canada. 

Canadian Journal of Botany 48: 1703-1726. 

Received 4 August 1976 
Accepted II October 1977 



Birds of the Coastal Zone of Melville Island, 1973-1975 

Lynda S. Maltby 

Canadian Wildlife Service, Ontario Region, 2721 Highway 31, Ottawa, Ontario KIG 3Z7 
Present address: Department of Biology, Carleton University, Ottawa, Ontario KIS 5B6 

Maltby, Lynda S. 1978. Birds of the coastal zone of Melville Island, 1973-1975. Canadian Field-Naturalist 92(1): 24-29. 

Observations of the birds along the coasts of Melville Island were obtained in the summers of 1973-1975. Thirty-eight 
species were recorded of which 21 were found breeding. Species recorded for the first time from Melville Island were Arctic 
Loon, Canada Goose, White-fronted Goose, White-winged Scoter, Least Sandpiper, and Semipalmated Sandpiper. New 
breeding records were obtained for Ruddy Turnstone, Semipalmated Sandpiper, and Arctic Tern. The lack of snow-free 
habitat in 1 974 prevented most waterfowl and shorebirds from establishing nests. Birds that did successfully rear young nested 
on sandstone outcrops or on high ridges that became free of snow earlier than the low-lying areas. 

Key Words: Northwest Territories, breeding birds, Melville Island, range extensions. 



During 1973-1975, while employed in an 
integrated landscape survey involving the 
Geological Survey of Canada, the Forestry 
Management Institute, and the Canadian Wild- 
life Service, I studied migratory birds on eastern 
Melville Island in the Arctic Archipelago. The 
purpose of this paper is to report observations of 
birds seen in the coastal zone of Melville Island. 
No specimens were collected; however, the close 
approach generally possible in the Arctic, 
coupled with my previous experience with all of 
these species in northern Canada, allowed 
certain identification of even those birds found 
beyond their known ranges. 

Localities Visited 

During the summers 1973-1975, aerial 
surveys were flown along the coasts of Melville 
Island to determine distribution and numbers of 
birds (Figure 1 ). Our base camps were at Sherard 
Bay from 5 July to 28 August 1973, at Consett 
Head from 20 June to 11 August 1974, and at 
Sabine Bay from 25 June to 30 July 1975. G.R. 
Parker contributed the records for Bailey Point 
in June-August 1974. Locations where extensive 
ground coverage took place are shown in Figure 
1. 

The coastal zone of Melville Island, for the 
purposes of this paper, includes areas up to 8 km 
inland from the coast. It contains a variety of 
different habitats: tundra ponds, lakes, high- 
centered polygons, poorly-drained grassy mea- 
dows, poor-to-well-vegetated alluvial ter- 
races, poor-to-well-vegetated discontinuous 
marine veneer (recent marine sediments, now 



above sea-level), beach ridges, braided streams, 
and coastal cliffs. Further information, clas- 
sification and description of habitats may be 
found in the report by Barnett et al. (1975). 

Results 

Thirty-eight species of birds were found on 
Melville Island during the study. In 1973 and 
1975 conditions were good. In 1974, spring was 
exceptionally late, and the snow cover was 
unusually deep owing to an above-average 
snowfall in the late winter and spring (D. C. 
Thomas, personal communication). When we 
arrived on 20 June 1974, there were no snow-free 
areas along the eastern coast of Melville Island. 
At Consett Head where we set up our main camp 
the only patch of open water was along the coast 
in the river valley. 

Table 1 summarizes the species of birds seen 
on Melville Island in one or more of the three 
years and compares their presence and breeding 
status with those listed by Godfrey (1966) and 
Snyder (1957). 

The following annotated list includes all 
species observed on Melville Island in 1973- 
1975. 

Arctic Loon {Gavia arctica). Breeds on Banks and 
Victoria Islands. On 1 July 1 973 four ( 1 , 1 , 2) in large 
bay along the southeastern coast near Beverly Inlet; 
first recorded for Melville Island. No evidence of 
breeding. 

Red-THROAted Loon {Gavia stellata). Bred in 1973 
and 1975 on tundra ponds and small shallow lakes; 
none bred in 1974. 



24 



1978 



Maltby: Birds of Melville Island, N.W.T. 



25 




Figure 1. The stippled strip represents routes of aerial surveys taken on Melville Island in 1973, 1974, 1975. Strips bordered 
by broken lines were surveyed only in 1973. The hatched areas show the locations covered by ground surveys in 
1973-1975. 



Canada Goose {Branta canadensis). Breeds north 
to Victoria Island. One at Eldridge Bay on 6 July 1973, 
and 11 on 26 July 1975 at Weatherall Bay, mixed with 
flocks of non-breeding Brant; first records for 
Melville Island. All were from the middle-sized stocks 
B.C. parvipes or taverneri, rather than the small 
minima or hutchinsii. 

Brant {Branta bemicla). Bred in 1973, average brood 
size 3.4 (range 2 to 5), and 1975, average brood size 3.2 
(range 1 to 7). Brood locations shown in Figure 2. All 
broods found in well vegetated areas. None bred in 
1974. Previously treated as two species or subspecies. 
the light-bellied or Atlantic Brant regarded as hrota 
and the dark-bellied or Black Brant as nigricans 
(Delacour 1954). Both forms breed on Melville Island 
but the majority were intermediate in color. 

White-fronted Goose {Anser albifrons). Breeds 
from northern Yukon to northern Keewatin and 
southern edge of Victoria Island. One at Sabine Bay, 6 
July 1975; first record for Melville Island. 

Snow Goose {Anser caerulescens). First record of 
breeding was in 1972 (Miller and Russell 1974). Bred 



in 1973, average brood size 4. 3 (range 1 to 6) and 1975, 
average brood size 4.8 (range 3 to 7). Brood locations 
shown in Figure 2. In 1974, 1 pair at the Hubbard 
Lake System and small flocks of two to seven from 27 
June to 6 July at Bailey Point; none known to have 
bred. Snow Geese handled at banding were 
A. c. atlantica (Greater Snow Goose). Melville Island 
is the most westerly part of known range of this form. 

Oldsquaw {Clangula hyemalis). Most were non- 
breeders; one brood on large lake at Little Point on 24 
July 1973. None known to have bred in 1974 or 1975. 

Common Eider {Somateria moUissima). Breeds on 
Cornwallis, Devon, and southern Ellesmere Islands. 
One female in tundra ponds at Sabine Bay 2-5 July 
1975; first confirmed record for Melville Island. 

King Eider {Somateria spectabilis). Bred success- 
fully in 1973 and 1975, primarily in small freshwater 
tundra ponds; breeding distribution shown in Figure 
2. Only one nest found, at King Point, 11 July 1974, 
with eggs destroyed by jaegers. 

White-winged Scoter {Melanitta deglandi). Breeds 



26 



The Canadian Field-Naturalist 



Vol. 92 



Table I- 



-Species of birds seen on Melville Island, 1973-1975 compared to species recorded by Godfrey (1966) and Snyder 
(1957). X = recorded, B = nest or brood found 



Species 



Melville Island 



1973 



1974 



1975 



Godfrey 
1966 



Snyder 
1957 



*Arctic Loon 

Red-throated Loon 

Fulmar (Fidmarus glacialis) 

Whistling Swan (Olor columbianus) 
*Canada Goose 
* White-fronted Goose 

Brant 

Snow Goose 

Oldsquaw 

Common Eider 

King Eider 
*White-winged Scoter 

Rough-legged Hawk 

Gyrfalcon 

Peregrine Falcon 

Willow Ptarmigan 

Rock Ptarmigan 

Sandhill Crane 

Ringed Plover (Charadrius hiaticula) 

American Golden Plover 

Black-bellied Plover 
**Ruddy Turnstone 

Red knot 

White-rumped Sandpiper 

Baird's Sandpiper 
*Least Sandpiper 

Dunlin 
**Semipalmated Sandpiper 

Sanderling 

Buff-breasted Sandpiper 

Red Phalarope 

Northern Phalarope (Lobipes lobatus) 

Pomarine Jaeger 

Parasitic Jaeger 

Long-tailed Jaeger 
Glaucous Gull 
Thayer's Gull 

Ivory Gull (Pagophila ebarnea) 
**Arctic Tern 

Black Guillemot (Cepphus grylle) 

Snowy Owl 

Horned Lark 

Common Raven 

Lapland Longspur 

Snow Bunting 

Number of species breeding 

Number of species 











X 










X 


X 




X 
X 






B 


X 


B 


B 


X 


B 


X 


B 


B? 


X 


B 


X 


X 
X 


B 


X 
X 


B 


X 
X 


B 


B 


X 


X 


X 




B 




X 






B 


X 


X 






B 


X 


B 


X 
X 




B 


X 

B 
B 




X 


X 


B 


B 


X 


B 


X 


B 


X 




B 


B 




X 


B 


X 


B 


B 


B 


X 


X 


B 


B 


B 


B 


X 

X 


X 
X 


B 


B 
X 


B 


X 


X 






B 


B 


X 
X 


B 
B? 


B 


B 


B 


B 


B 


B 
X 


B 


X 


X 


B 


B 


X 


X 


X 


B 


B 


B 


B 


B 


B 


B 


B 


X 


B 


B 


B 


X 


X 




B 


B 


B 


B 


B 




X 
X 


X 


X 
B 


X 


B 
B 


B 


X 


X 


X 


B 


X 


B 


B 


B 


B 


B 


B 


B 


B 


B 


B 


17 


9 


13 


26 


16 


28 


30 


28 


27 


34 



' First sight records for Melville Island, Northwest Territories 
•New breeding records for Melville Island. Northwest Territories 



1978 



Maltby: Birds of Melville Island, N.W.T. 



27 




Legend 

1973 1975 

Brant A A 

Snow Geese ^ O 

K.ng Elder _ Q 



Figure 2. Locations of broods of Brant, Snow Geese, and King Eiders sighted on Melville Island in 1973 and 1975. 



in Yukon and western Mackenzie, southern Keewatin 
and southward. One pair at Consett Head 12 July 
1974; first record for Melville Island. 

Rough-legged Hawk (Buteo lagopus). One at 
Dundas Peninsula 10 July 1973; one at Bailey Point 
26 June and 3 July 1974; both were dark-phase 
birds. None seen in 1975. 

Gyrfalcon {Falco rusticolus). One seen 6 km inland 
at Sherard Bay, 9 July 1973. No evidence of breeding. 

Peregrine Falcon (Falco pereghnus). Suspected 
nesting around Winter Harbour and Dundas 
Peninsula in 1961 (Tener 1963). One near coastal cliffs 
and hills 800 ft elevation on Dundas Peninsula 10 July 
1973. None seen in 1974 or 1975. 

Rock Ptarmigan {Lagopus mutus). Bred in 1973. 
No young seen in 1974, and no ptarmigan seen in 
1975. Both Willow Ptarmigan {Lagopus lagopus) and 
Rock Ptarmigan suspected to breed on Melville 
Island (Godfrey 1966); all seen and heard by us were 
Rock Ptarmigan. 

Sandhill Crane {Grus canadensis). Suspected 
breeding at Winter Harbour (Snyder 1 957). One from 
26 June to 1 August 1974 at Bailey Point. None seen in 
1973 or 1975. No evidence of breeding. 



American Golden Plover {Pluvialis dominica). 
None seen in 1973. Two courting near Consett Head, 
1 1 July 1974; two near tundra ponds, Sabine Bay, 25 
June 1975. No nest or young found. 

Black-bellied Plover {Pluvialis squatarola). One 
pair and one bird at Winter Harbour 8 July 1973, and 
one pair at Robertson Point 10 July 1973. One pair 
with nest and four eggs at Bailey Point 30 June to 25 
July 1974; hatching on 25 July. Two at Sabine Bay 23 
June 1975. 

Ruddy Turnstone {Arenaria interpres). None seen 
in 1973. One adult with two fledged young at Bailey 
Point 10 July 1974, and on 4 July 1975 one adult with 
three young 4 km inland from Sabine Bay; first 
breeding records from Melville Island. Race on 
Melville Island not yet determined; A.i. interpres is 
found to north and east, and A.i. morinella to the 
south and west (Godfrey 1966). 

Red Knot (Calidris canutus). One nest with four 
eggs near tundra ponds at Sherard Bay on 1 1 July, and 
four broods (4, 4, 4, and 3 young) at Little Point, 12 
July 1973. No nests or young found in 1974. Bred at 
Robertson Point in 1975. Race on Melville Island not 
yet determined; C.c. canutus breeds on Ellesmere 
Island; C.c. rufa breeds to south and east (Godfrey 
1966). 



28 



The Canadian Field-Naturalist 



Vol. 92 



White-rumped Sandpiper {Calidhs fuscicollis). 
None found breeding in 1973 or 1974. Likely bred at 
Sabine Bay in 1975. 

Baird'S Sandpiper {Calidris bairdii). One brood (1 
adult, 2 young) near lake at Little Point, 24 July 1973. 
None found breeding in 1974 or 1975. 

Least Sandpiper {Calidhs minutilla). Breeds in 
Yukon, southern Keewatin, and east to Southampton 
Island; suspected breeding on southern Victoria 
Island. One pair at Sabine Bay 30 June 1975; first 
record for Melville Island. No nests or young found. 

Dunlin {Calidris alpina). Reported on southern 
Melville Island by Snyder (1957). Two separate birds 
near Little Point on 22 July 1 974. None seen in 1 973 or 
1975. 

Semipalmated Sandpiper {Calidris pusilla). 
Known to breed only as far north as Banks and Victoria 
Island. On 23 July 1973 one adult with four young at 
Little Point; first records of occurrence and breeding 
for Melville Island. A few seen in 1974 and 1975, but 
no breeding detected. 

Sanderling {Calidris alba). Two adults with four 
young at Little Point 24 July 1973 and one adult with 
two newly fledged young at Bailey Point on 7 August 

1974. Many seen in 1975 but none found breeding. 

Buff-breasted Sandpiper {Tryngites subruficollis). 
None seen in 1973 or 1974. Four displaying near 
tundra ponds at Sabine Bay on 23 July 1975. No 
evidence of breeding. 

Red Phalarope {Phalaropus fulicarius). Two 
broods in tundra ponds at Sherard Bay 19 July (two 
adults with two young) and 2 1 July (one male with one 
young) in 1973. Bred at Bailey Point in 1974; a male 
with a nest with four eggs found on 1 2 July 1 974. Bred 
in 1975 at Sabine Bay in area containing many tundra 
ponds. 

Pomarine Jaeger {Stercorarius pomarinus). Nest 
found 11 July 1973 near tundra ponds, and on 14 July, 
two adults and two young on alluvial terraces at 
Sherard Bay. Four seen in 1974. Only one observed in 

1975. Both light and dark phases present. 

Parasitic Jaeger {Stercorarius parasiticus). Nine 
singles seen on beach ridges near Weatherall Bay 10 
July 1973, and one near tundra ponds at Sabine Bay 
in 1975. None seen in 1974. Not likely breeding. All 
light phase. 

Long-tailed Jaeger {Stercorarius longicaudus). 
Common: bred in all 3 years on Melville Island. Four 



broods (ranging from 1 to 2), and two nests both with 
three eggs seen in 1973; three-egged clutches are 
unusual for this species (D.J.T. Hussell, personal 
communication) and have not been found elsewhere 
in the Arctic. 

Glaucous Gull {Larus hyperboreus). Common on 
Melville Island. In 1973 and 1975 most nests found in 
small colonies on stacks along coastal cliffs of Dundas 
Peninsula and Weatherall Bay. None bred in 1974. 

THAYER'S Gull {Larus thayeri). Only three identified 
in 1973, one in 1974, and none in 1975; all along the 
coast between Burnett Point and Ross Point. None 
found breeding. 

Arctic Tern {Sterna paradisaea). A colony of 75 on 
Dealy Island 10 July 1973 and a large colony of 
undetermined nesting status on a small island east of 
Cape Bounty, as well as several pairs breeding at the 
mouths of rivers, were first breeding records for 
Melville Island. Bred in 1974 at Consett Head and 
Bailey Point, but not at Dealy Island which was snow- 
covered. A colony of 250 terns bred at Dealy Island in 
4975. 

Snowy Owl {Nyctea scandiaca). Many owls seen but 
no nests or young found in 1973-1975. 

Horned Lark {Eremophila alpestris). On 25 June 
1974 three feeding 6 km inland from coast at Consett 
Head and 7 July four seen near Rae Point. Nest with 
six eggs found 6 July 1974 at Bailey Point. None seen 
in 1973 or 1975. 

Common Raven {Corvus corax). A total of 21 seen; 
many attracted to garbage dumps around camps. No 
young or nests found. 

Lapland Longspur {Calcarius lapponicus). Bred in 
all 3 years. Seen mainly around lakes and tundra 
ponds on beach rides. 

Snow Bunting {Plectrophenax nivalis). Bred all 3 
years. Most clutches consisted of four eggs or young. 
Little affected by adverse weather conditions in 1974. 



Discussion 

Many avifaunal lists have been compiled for 
Canada's Arctic islands, but most have been 
based on a single season's work. Longer-term 
studies have been mostly on the breeding biology 
of a single species, and particularly of Arctic- 
nesting geese. The fact that such Arctic geese 
experienced years in which no reproduction at 
all took place has been known for at least two 



1978 



Maltby: Birds of Melville Island, N.W.T. 



29 



decades, and 1974 was only the latest example of 
such years. This study, however, is perhaps the 
first to show the extent to which such adverse 
seasons affected reproduction of birds other 
than geese; moreover, it provides data for two 
other, more or less normal seasons for com- 
parison. 

In 1974, the lack of snow-free habitat pre- 
vented most waterfowl and shorebirds from 
estabhshing nests. Of the five species of water- 
fowl and loons seen in all three years, all bred in 
1973, none in 1974, and four were known to have 
done so in 1975. The pattern is less clear for 
shorebirds, probably because breeding evidence 
was harder to obtain; five, four, and four species, 
respectively, of shorebirds bred in the three 
years. For jaegers, gulls, and terns, the yearly 
totals breeding were four, two, and three, and 
the two ubiquitous passerines bred each year. 
The species that were able to breed successfully 
in 1974 were those that nested in snow-free 
situations such as ridges, outcrops, river-mouth 
flats, but a few individuals of other species bred 
in locally snow-free areas like Bailey Point. 

This paper lists five species not previously 
reported for Melville Island, of which one — 
with two other species — represents new 
breeding records for the island. This study 
obtained records of five species, which were 
listed for Melville Island by Snyder (1957) but 
which were not accepted by Godfrey (1966). It 
seems possible that further field work would 
substantiate some of the six other species shown 
by Snyder but as yet unconfirmed. 



Acknowledgments 

This study was supported financially by the 
Canadian Wildlife Service. Thanks go also to 
Martin Barnett and Patrick McLaren of the 
Geological Survey of Canada, Grant Wyatt of 
Klondike Helicopters, personnel of the Polar 
Continental Shelf Project in Resolute, and my 
field assistants, George Finney (1973), Sandra 
Dodd and Andrew St. -Joseph ( 1 974), and Lynne 
Allen and Barbara Campbell (1975). R.H. 
Kerbes and Hugh Boyd encouraged the initia- 
tion and continuation of the study and they, with 
A. J. Erskine, also of Canadian Wildlife Service, 
and W. Earl Godfrey and Stewart MacDonald 
of the National Museums of Canada, offered 
useful comments on the manuscript. 

Literature Cited 

Barnett, P. M., S. A. Edlund, L. A. Dredge, D. C. Thomas, 

and L. S. Prevett Maltby. 1975. Terrain classification 

and evaluation, eastern Melville Island, N.W.T. Volumes 

1 and 2. Geological Survey of Canada, Open File 252. 747 

pp. and 571 pp. 
Delacour, J. 1954. The waterfowl of the world. Volume 1. 

Country Life Ltd., London, pp. 183-194. 
Godrey, W. Earl. 1966. The birds of Canada. National 

Museum of Canada Bulletin 203: 
Miller, F. L. and R. H. Russell. 1974. Snow Geese nesting 

on Melville Island, Northwest Territories. Canadian 

Field-Naturalist 88: 91. 
Snyder, L. L. 1957. Arctic birds of Canada. University of 

Toronto Press, Toronto. 309 pp. 
Tener, J. S. 1963. Queen Elizabeth Islands Game Survey 

1961. Canadian Wildlife Service, Occasional Papers 

Number 4. p. 50. 

Received 26 July 1976 
Accepted 21 October 1977 



Above-ground Biomass of Vascular Plants in a 
Subarctic James Bay Salt Marsh 



Walter A. Glooschenko 

Canada Centre for Inland Waters, Box 5050, Burlington, Ontario L7R 4A6 

Glooschenko, Walter A. 1978. Above-ground biomass of vascular plants in a subarctic James Bay salt marsh. Canadian 
Field-Naturalist 92(1): 30-37. 

Vegetation studies including determination of species composition and cover were made along a transect in a subarctic salt 
marsh located on the southwestern coast of James Bay, Ontario, Canada. Eight vegetation zones were recognized from an 
intertidal colonization area dominated by Puccinellia phryganodes to the edge of a willow thicket at the landward end of the 
marsh complex. In each zone, above-ground biomass of vascular plants was determined by clipping at the time of peak 
biomass. Values ranged from an estimated low of 29 g/m^ dry weight on gravel beach ridges and 1 57 g/m- in the mid-marsh to 
a high of 569 g/ m- in the zone nearest the willow thicket, which was dominated by Juncus balticus. A weighted-mean above- 
ground biomass for the transect was 357 g/ m^, taking into account the biomass and the width of these zones. The biomass 
values found in this study were lower than reported in the literature for salt marshes located on the Atlantic coast of North 
America between Georgia and Nova Scotia but were higher than those reported for Swedish salt marshes located on the Baltic 
Sea. 

Key Words: salt marsh, James Bay, vegetation, above-ground biomass, subarctic, Ontario. 



The western coast of James and Hudson Bays 
south of Churchill, Manitoba, is characterized 
by extensive salt-marsh development. Physio- 
graphically, the coastal area consists of long 
stretches of relatively straight shorelines which 
are fairly flat in relief, averaging 0.6 m/km in 
terms of slope. This flat topography allows high 
spring and fall tides to extend inland for as much 
as several kilometres in some areas especially 
when such tides are accompanied by high winds 
off the bay. Coastal features such as beach ridges 
formed by isostatic uplift (Moir 1954) act to trap 
sediments, thus stabilizing the substrate for 
vegetative growth. Such features also restrict the 
flow of tidal waters inland, thus controlling the 
width of salt marshes. Also, usually the salt 
marsh grades into a freshwater marsh/ fen 
complex. 

Little work has been done on the vegetation 
ecology of such salt marshes. Previous studies 
have dealt mainly with floristic aspects (Dutilly 
et al. 1954; Porsild 1957; Schofield 1959). The 
only ecologically-oriented study of salt marshes 
in the area was done by Kershaw (1976) who 
studied vegetational zonation in salt marshes at 
East Pen Island on Hudson Bay, which is located 
just south of the Manitoba-Ontario border. 
Owing to the lack of ecological studies in these 
salt marshes, a study was begun of vegetational 
composition and structure at North Point, 



Ontario, on James Bay (51°29'N, 80°27'W), 
which is located approximately 27 km NE of 
Moosonee, Ontario (Figure 1). 

This area was chosen because it is the site of a 
Canadian Wildlife Service shorebird migration 
research project; the coast is a very important 
waterfowl flyway. Climatic data are not avail- 
able at North Point, but data available for 
nearby Moosonee indicate that area has a 
growing season (period when mean daily 
temperatures are above 5.6° C) of approximately 
143 days starting in mid-May and running 
through the first week of October. Temperatures 
of below 0°C, however, can occur until 19 June 
and after 27 August on the average. Winter 
temperatures average -21 to -23° C, and an all- 
time low of ^7° was recorded in Moosonee. 
Summers are warm with an average July 
temperature of 16°C. Yearly precipitation is 
76 cm, of which approximately one third occurs 
as snow (Chapman and Thomas 1968; Thomp- 
son 1968). This precipitation is divided fairly 
evenly over the year. The area is classified 
climatologically as subarctic and the dominant 
upland vegetation is typically northern boreal 
forest with large inland areas of bog and fen 
vegetation (Hustich 1957). 

The purpose of this paper is to report on the 
above-ground biomass of plants with emphasis 
on estimates for recognized salt-marsh zones in 



30 



1978 



GLOOSCHENKO: PLANT BlOMASS, JAMES BAY 



31 




100 200 



SCALE 
Km 



LIMIT OF 

HUDSON 

BAY 

LOWLANDS 



\ QUEBEC 



Figure 1. Map of Hudson Bay Lowlands showing North Point, site of salt marsh study. 



the North Point study area. A detailed analysis 
of the vegetation structure of the North Point 
salt marshes is in progress. 

Methods 

Three transects perpendicular to the shore 
were set up by surveying with a transit and stadia 
rod. This was done before the beginning of 
vegetative growth in mid-May 1976. These 
transects were approximately 1 km in length and 
ran from the intertidal zone seaward of plant 
colonization to the edge of a well defined willow- 
thicket vegetation zone located on an old beach 
ridge that marked the termination of the salt- 
marsh complex at North Point. A profile of this 
is shown in Figure 2. Owing to an absence of 
bench marks in the area all elevations are 
relative. Vegetation analysis was done on the 
transects during 11-13 August 1976 coinciding 
with the time of apparent peak biomass. Other 
salt marsh studies have indicated that peak 
above-ground biomass in salt marshes occurs 
from late July to mid- August (Tyler 1971 ; Keefe 
and Boynton 1973; Wallentinus 1973; Hatcher 
and Mann 1975). At 10-m intervals a quadrat 
(1X1 m), was placed on the transect and all 
species of plants were recorded with an esti- 



mation of percent cover using Braun-Blanquet's 
scale (Poore 1955). Sources of plant species 
names were Gleason and Cronquist (1963) and 
Porsild (1973). From the results, eight fairly 
distinct zones of vegetation were present from 
the lower intertidal zone to the edge of the willow 
thickets. As a result of a lack of time only one 
transect was chosen for above-ground biomass 
studies. In each zone, up to five random tosses of 
a 0.125-m^ rectangular quadrat (25 X 50 cm) 
were made and on each site all above-ground 
vegetation including attached dead plant parts 
was clipped with lawn shears. Last year's carry- 
over of dead plant litter was excluded. On the 
gravel beach ridges, vegetative cover was esti- 
mated to be 5% of the total area. To estimate 
biomass here, sites of 100% vegetation cover 
were clipped, dry weights determined, and the 
average dry weight multiplied by 5% to get a 
rough cover estimate for the gravel ridge zone. 
The plant material thus obtained was placed in a 
paper bag and allowed to air-dry until return to 
the laboratory. There, samples were oven-dried 
for 48 h at 80° C, allowed to cool to room 
temperature, and the dried vegetation was 
weighed to the nearest 0.1 g. From this, weights 
were converted to a grams dry-weight per square 



32 



The Canadian Field-Naturalist 



Vol. 92 



<r 




> 




LU 


^ 


_l 


V) 


LU 


}U 






LU 

> 


E 


^ 




J 




111 




DC 






JAMES 
BAY 



100 200 300 400 500 600 700 800 900 1000 1100 

DISTANCE (metres) 

Figure 2. Profile of transect with relative elevation in metres. Arrow depicts mean high-tide line as evidenced by 
accumulation of dead benthic algae such as Fucus spp. and dead Zostera marina. 



metre basis. This is the same definition of above- 
ground biomass as used by Tyler ( 1 97 1 ), Wallen- 
tinus (1973), and Hatcher and Mann (1975). 

Results 

Topographically the only significant relief 
occurring in the area of the transect occurs in the 
form of two beach ridges (Figure 2). The most 
seaward of these ridges has a height of 1 .6 m on 
its foreshore face, a base width of 25 m, and a 
backshore height of 1 .0 m. The ridge is made up 
of angular pebbles formed by freezing and 
thawing processes. The second smaller ridge was 
located 140 m landward of the main ridge, was 
9 m in width and 0.25 m higher than the 
surrounding land surface. Seaward of the main 
ridge, the transect was extended 340 m to the 
outermost beginning of colonization of the inter- 
tidal area by vegetation, in this case sparse 
Puccinellia phryganodes. There are some sites 
seaward of this point, however, where Zostera 
marina was observed to occur. The difference of 
elevation over this distance was only 0.4 m 
(1.2 m/km). The inter-ridge area was flat, and 
landward of the second ridge, a gradual slope of 
0.4 m over a 290-m distance was noted 
(1.4 m/km). Thus the area is very flat, and 
during a high-tide period in late August 1976, 
water came inland approximately 450 m beyond 
the main ridge. Previous to that, the highest tides 
came only as far as the seaward face of the main 
ridge. Thus the ridges tend to act as a barrier to 
the landward movement of tidal waters and are 
therefore an important ecological feature in 
controlling the extent of salt-tolerant plant 
species. 



Vegetation data from the clipping quadrats 
including above-ground biomass, species com- 
position, percent cover, and width of vegetative 
zone, are presented in Table 1 . The most seaward 
zone is the lower intertidal zone in which 
colonization by vascular plants occurs, mainly 
Puccinellia phryganodes. This area is character- 
ized by a turf-like appearance with fairly 
complete vegetative cover with the exception of 
very shallow pond-like depressions, which 
appear to be caused by scouring by ice action. 
No ponds were located in the clipping quadrats, 
but they often contain Ruppia maritima. Scir- 
pus maritimus occurs on the pond edges, along 
with Triglochin maritima and very sparse 
Suaeda maritima. As one gets higher up the 
profile towards the beach ridges into the upper 
intertidal zone (Zone 2), development of small 
depressions, characterized by high-salt content 
due to evaporation, known as pannes, occur. 
Here Plantago maritima becomes quite abun- 
dant along with Atriplex glabriuscula, Glaux 
maritima, Salicornia europaea, Triglochin mari- 
tima, and some Potentilla egedii even though 
these did not necessarily occur in the quadrats 
that were clipped. 

Both ridges are included in Zone 3 and are 
characterized by very sparse vegetation, mainly 
Elymus mollis in large clumps with some rosettes 
of Honkenya peploides and Mertensia mari- 
tima. A rough estimate of above-ground bio- 
mass on these ridges would be approximately 
29 g/ m2 by the method previously described. 

The area between the ridges (Zone 4) is fairly 
productive and characterized by the species 
Potentilla egedii and Hordeum jubatum. Some 



1978 



GLOOSCHENKO: PLANT BlOMASS, JAMES BAY 



33 



Table 1 — Above-ground biomass data for North Point Salt marsh zones. For cover estimate, + = 1%, 1 = 1-5%, 2 = 5-25%, 

3 - 25-50%, 4 = 50-75%, 5 = > 75% 



Zone 



Above-ground 

biomass, 
g-m~^ dry wt 



Width 

of 
zone, m 



Vegetation with Braun-Blanquet cover estimate 



(1) Intertidal 


373.6 


colonization 


515.2 




288.0 




360.8 




421.6 




Mean 391.8 




SD 83.9 


(2) Upper 


270.4 


intertidal 


326.4 



289.6 

349.6 

Mean 309.0 
SD 35.7 



Puccinellia phryganodes (5) 
Puccinellia lucida (3), P. phryganodes (3) 
160 P. phryganodes (5) 

P. phryganodes (5), Glaux maritima (2) 
P. phryganodes (5), Scirpus maritimus (2) 



Plantago maritima (5), Puccinellia phryganodes (3) 

Puccinellia phryganodes (5), Plantago maritima (3), Salicornia 

europea (+) 
Plantago maritima (4), Puccinellia phryganodes (3), Atriplex glabri- 

uscula (4), Salicornia europaea (4) 
G. maritima (4), Plantago maritima (2) 



(3) Ridges 



(4) Interridge 



381.6 
332.8 

460.0 
314.4 

263.2 

228.0 







Mean 


330.0 






SD 


83.3 


(5) 


Triglochin- 




136.0 




Po tent ilia 




188.0 
144.0 
206.4 

117.6 






Mean 


158.6 






SD 


37.4 


(6) 


Carex 




313.6 




paleacea 




526.4 
467.2 
401.6 






Mean 


431.4 






SD 


79.6 



30 Note: Assuming 5% total vegetative cover of beach ridges, biomass 

estimated to be 29 g/ m^. This is based upon clipping three clumps of 
Elymus mollis (100% cover), getting values of 504.0, 616.0, and 
600.8 g/m^, average = 573.6 g/m^ and multiplying by 5% 

Potentilla egedii (5), Hordeum jubatum (+), Atriplex patula (+) 

Potentilla egedii (5), H. jubatum (2), A. patula (+). Salicornia 
europaea (+) 
50 Potentilla egedii (4), H. jubatum (2), A. patula (+) 

Puccinellia lucida (3), Plantago maritima (2), H. jubatum (\), Poten- 
tilla egedii (1), Salicornia europaea (+) 

Plantago maritima (3), A. patula (2), H. jubatum (1), Potentilla 
egedii (1), Puccinellia lucida (1) 

Potentilla egedii (4), Puccinellia lucida (3), H. jubatum (2) 



A. patula (3), H. jubatum (2), Potentilla egedii (1), Puccinellia 

lucida (+) 
Triglochin maritima (4), Potentilla egedii (3), Aster novi-belgii (+) 
160 Potentilla egedii (4), T. maritima (2), Plantago maritima (1) 

T. maritima (3), Potentilla egedii (2), Plantago maritima (1), A. 

patula (+), Puccinellia lucida (+), Salicornia europea (+) 
Plantago lucida (2), T. maritima (2), H. jubatum (4), A. patula (4) 



Carex paleacea (4), Potentilla egedii (1), G. maritima (4), T. 

maritima (4) 
C. paleacea (5), T. maritima (4) 
C. paleacea (5), T. maritima (1), Potentilla egedii (4) 
170 C paleacea (2), 7". maritima (2), Potentilla egedii (I), G. maritima (A) 



Continued on next page 



34 



The Canadian Field-Naturalist 



Vol. 92 



Table 1 continued 





Above-ground 


Width 




biomass. 


of 


Zone 


gm ' dry wt 


zone, m 


(7) Scirpus 


188.8 




ponds 


185.6 






308.8 


40 




Mean 227.7 






SD 70.2 




Juncus 


539.2 
495.2 






703.2 


90 



Vegetation with Braun-Blanquet cover estimate 



599.2 

Mean 569.0 
SD 85.1 



5. maritimus (2), T. maritima (4) 
S. maritimus (2) 
5. maritimus (3) 



Cicuta maculata (2), Aster novi-belgii (2), Juncus balticus (2), 
Potentilla egedii (2), Galium labradoricum (+), Poa spp. (+) 

C. maculata (2), Parnassia palustris (2). Rhinanthus Crista-galli (2), 
J. balticus (2), T. maritima (+), Poa spp (+) 

/. balticus (5), Potentilla egedii {2), T. maritima (l), C. maculata (\), 
Lathyrus palustris (I), C maculata (2), C. paleacea (2), Potentilla 
egedii (2), T. maritima (2), Ranunculus cymbalaria (+), Eleocharis 
palustris (+) 

/l.yrer novi-belgii (3), /. balticus (2), Potentilla egedii (2), G. 
labradoricum (+) 



sites within this inter-ridge zone are occupied by 
A triplex patula and Salicornia europaea, 
especially where salinities of the soil appear to be 
elevated, as indicated by the presence of salt 
crusts on the surface. Landward of the ridges 
was the least productive area. Zone 5, charac- 
terized by sparser distribution of vegetation, 
mainly Triglochin maritima and Potentilla 
egedii. This zone was fairly dry during most of 
summer until the high tides of late August 
inundated it. Also, salt crusts occurred in some 
parts of the zone; hence it may be lower in 
productivity because of its arid nature and 
possibly increased soil salinity. This hypothesis 
is the subject of further investigation. Figure 3 
illustrates this zone. 

Landward of this zone are two wetter environ- 
ments, a clearly defined zone of Carex paleacea 
(Zone 6) and a series of ponds dominated by 
Scirpus maritimus (Zone 7). The Scirpus ponds 
did not have a very high above-ground biomass, 
228 g/ m2, but they were rich in benthic algae and 
often contained the aquatic macrophytes Hip- 
purus vulgaris and Zannichellia palustris. This 
algal community was not sampled; hence, the 
Scirpus biomass is an underestimate for the 
zone. 

The last zone (8) was dominated visually by 
Juncus balticus and Cicuta maculata. This zone 



had some wet depressions in which Potentilla 
egedii and Triglochin maritima were found. In 
general, however, the zone was characterized by 
terrestrial species. The zone ended in a willow 
thicket dominated by Salix bebbiana and 5'. 
Candida; however, the beginning of the willow 
thickets was not a sharp transition but was 
characterized by scattered willows. The willow 
thicket was located on an old beach ridge with 
weak soil development. In some areas of the 
willow thicket, freshwater marshes occurred, 
characterized by such species as Typha latifolia, 
Carex rostrata, C. aquatilis, Petasites sagittatus, 
Equisetum fluviatile and others. The willow 
thicket and freshwater marshes gave way to 
treed fen including Picea mariana, Picea glauca, 
Populus balsamifera, and Larix laricina. Some 
graminoid fen areas also were present, but in the 
present study only the salt marsh vegetation was 
considered, and biomass measurements were 
stopped at the thicket. 

Discussion 

Two points merit discussion, namely the 
distribution of biomass in the marsh, and a 
comparison of the North Point salt marsh with 
other published biomass data for salt marshes. 
The highest biomass, 569 g/m^, occurred in the 
uppermost zone studied (Zone 8), which was 



1978 



GLOOSCHENKO: PLANT BlOMASS, JAMES BAY 



35 





Figure 3. Photograph of Zone 5. Area in foreground is documented by Plantago marilima while Triglochin maritima 
and Potentilla egedii are adjacent to it. Boreal forest is in background. 



dominated by Juncus balticus, Cicuta maculata, 
and other more terrestrial species. A possible 
explanation for this higher biomass is that 
vegetative growth begins relatively early in this 
zone as observed in May by the presence of 
unidentifiable green shoots up to 5 cm in height. 
During the third week of May 1976, vegetation 
was already growing in this zone and on the 
beach ridges (Zone 3), while in Zones 4-7, the 
ground was still frozen several centimetres below 
the surface and only a few vegetative shoots or 
rosettes had started to appear above ground, 
mainly Puccinellia lucida. The intertidal area, 
Zones 1 and 2, was still covered by ice for the 
most part. In mid-May 1977, ice was not present 
in Zone 1 and Puccinellia phyrganodes had 
started to grow, with blades up to 2 cm in length. 
Thus, it appears that Zone 8 may be character- 
ized by a longer growing season. 

Next to Zone 8, the Carex paleacea zone 
(Zone 6) had highest above-ground biomass 
closely followed by Zone 1 (lower intertidal). 
The lowest biomass values were obtained in the 
xeric beach ridges; next lowest is Zone 5 which 
tends to be xeric and possibly higher in salt 
content, based upon visual observations. Thus it 
appears that important factors determining the 



distribution of productivity at North Point 
include length of growing season as influenced 
by soil and sediment temperature, soil moisture 
regime, and salinity. 

Comparing North Point data with other 
available data for salt marsh above-ground 
biomass. Table 2 was compiled using only more 
northerly salt-marsh data. A weighted mean 
above-ground biomass was calculated using 
width of zones and biomass of each zone for 
North Point excluding the beach ridges. This 
weighted mean was 357 g/m^ with a range of 
29 599g/m2. This appears somewhat lower 
than values found in North American Atlantic 
coast salt marshes, but is higher than that 
determined for two Swedish Baltic Sea salt 
marshes. None of the authors previously cited 
used this weighted-mean calculation, but simply 
used either a range of biomass values or an 
average (see Table 2). I feel, however, that such 
weighting techniques give a better idea of above- 
ground biomass in the salt-marsh complex. Of 
course, zone widths can vary. A simple mean, 
neglecting zone widths, is 344 g/ m^ which is very 
close to the weighted-mean. Thus values deter- 
mined in this study appear reasonable. Even 
though James Bay is subarctic in nature, the 



36 



The Canadian Field-Naturalist 



Vol. 92 



Table 2 — Above-ground biomass data for selected salt marshes 



Author 



Geographic locality 



Vegetation 



Above-ground 

biomass 

(dry wt- g-m~^) 



Keefe and Boynton (1973) Chincoteague Bay, 

Maryland-Virginia, USA 



Udell etal. (1969) 



Wallentinus(1973) 



Tyler (1971) 



Glooschenko (this study) 



Long Island, N.Y., USA 



Hatcher and Mann (1975) Nova Scotia, Canada 



Baltic Sea, 
S. Sweden 



Baltic Sea, 
S. Sweden 



North Point, Ontario 
James Bay 



Spartina allerniflora, 
Distichlis spicata 

Spartina alterniflora, 
Spartina patens, 
Distichlis spicata 



Spartina alterniflora 



Juncus gerardi, 

Agrostis stolonifera, 
Plantago maritima, 
Festuca rubra, 
Triglochin maritima, 
Glaux maritima 

Juncus gerardi, 

Eleocharis uniglomis, 
Agrostis stolonifera, 
Triglochin maritima, 
Glaux maritima, 
Plantago maritima 

See Table 1 



427-558 



508-827 

503 

648 

(average value for 
several sites of 
each species) 

448-762 

(average = 558) 

324 



161 



228-569. Mean is 
344 with a weighted 
mean based upon 
zone width of 357 



values determined are not a great deal lower than 
for more southerly coastal marshes in Nova 
Scotia and U.S. Atlantic coast states. 

As an indication of net primary production 
rates in the salt marsh the works of Tyler (1971) 
and Wallentinus (1973) in Baltic Sea salt 
marshes are of interest, where values of 230 and 
430 g-m"^-yr'', respectively, were found. The 
ratio of these net production values to biomass 
are 1.43 and 1.33. If we use 1.4 as an approxi- 
mate ratio of net production to biomass the 
North Point ranges of net primary production 
excluding the beach ridge would be 222- 
797 g-m~ -yr"' having a mean of about 
500 g-m"^-yr~'. This would place the North Point 
salt marshes ahead in productivity of such 
ecosystems as lakes and streams and most 
oceanic and tundra ecosystems, but below 
temperate grasslands in productivity (Whittaker 



1975; Coupland 1975). Such salt marshes would, 
however, be somewhat less productive than 
boreal forests. These salt marshes would also 
exceed the productivity of most arctic ecosys- 
tems (Wein and Rencz 1976; Wielgolaski 1975). 
Future studies in the area will emphasize above- 
ground productivity measurements in relation to 
soil chemistry. 

Acknowledgments 

I thank Tanya Mayer for her assistance in 
determining biomass weights, R. I. G. Morrison 
of the Canadian Wildlife Service for his assis- 
tance and hospitality at the James Bay Goose 
Camp at North Point, Yvon Desjardins for the 
surveying of the transects and his wife Val for 
assistance in vegetation surveys. The pilots of 
Great Lakes Helicopters at Moosonee, Ontario 
are also thanked for their flights to North Point. 



1978 



GLOOSCHENKO: PLANT BlOMASS, JAMES BAY 



37 



Literature Cited 

Chapman, L. T. and M. K. Thomas. 1968. The climate of 
northern Ontario. Department of Transport and Clima- 
tological Studies, Meteorological Branch, Number 6. 
58 pp. 

Coupland, R. T. 1975. Productivity of grassland ecosys- 
tems. In National Academy of Science productivity of 
world ecosystems. United States National Academy of 
Science, Washington, D.C. pp. 44^9. 

Dutilly, A., E. Lepage, and M. Duman. 1954. Contri- 
bution a la flore du versant occidental de la Baie James, 
Ontario. Catholic University of America Press, Washing- 
ton, D.C. 104 pp. 

Gleason, H. A. and A. Cronquist. 1963. Manual of vas- 
cular plants of northeastern United States and adjacent 
Canada. D. Van Nostrand, New York. 810 pp. 

Hatcher, B. G. and K. H. Mann. 1975. Above-ground 
production of marsh cordgrass (Spartina allerniflora) 
near the northern end of its range. Journal of the Fisheries 
Research Board of Canada 32: 83-87. 

Hustich, I. 1957. On the phytogeography of the subarctic 
Hudson Bay lowland. Acta Geographica 16: 1-48. 

Keefe, C. W. and W. R. Boynton. 1973. Standing crop of 
salt marshes surrounding Chincoteague Bay, Maryland- 
Virginia. Chesapeake Science 14: 117-123. 

Kershaw, K. A. 1976. The vegetationalzonation oftheEast 
Pen Island salt marshes, Hudson Bay. Canadian Journal 
of Botany 54: 5-13. 

Moir, D. R. 1954. Beach ridges and vegetation in the 
Fludson Bay region. Proceedings of the North Dakota 
Academy of Science 1954: 45^8. 

Polunin, N. 1948. Botany of the Canadian eastern Arctic. 
Part HI. Vegetation and ecology. National Museum of 
Canada Bulletin Number 104. 304 pp. 

Poore, M. E. D. 1955. The use of phytosociological 
methods in ecological investigations. I. The Braun- 



Blanquet system. Journal of Ecology 43: 226-244. 

Porsild, A. E. 1973. Illustrated flora ofthe Canadian Arctic 
Archipelago (1957). National Museum of Canada 
Bulletin Number 146. 

Schofield, W. E. 1959. The salt marsh vegetation of 
Churchill, Manitoba, and its phytogeographic implica- 
tions. National Museum of Canada Bulletin Number 160: 
107-132. 

Thompson, H. A. 1968. Climate. In Science, history, and 
Hudson Bay. Volume 1. Edited by C. S. Beals. Canadian 
Department of Energy, Mines, Resources, Ottawa, 
pp. 263-286. 

Tyler, G. 1971. Distribution and turnover of organic matter 
and minerals in a shore meadow ecosystem. Oikos 22: 
265-291. 

Udell, H. F., J. Zarudsky, T. E. Doheny, and P. R. Burk- 
holder. 1969. Productivity and nutrient values of plants 
growing in the salt marshes of the town of Hempstead, 
Long Island. Bulletin of the Torrey Botanical Club 96: 
42-51. 

Wallentinus, H. G. 1973. Above ground production of a 
Juncetum gerardi on a Baltic Sea-shore meadow. Oikos 
24: 200-219. 

Wein, R. W. and A. N. Rencz. 1976. Plant cover and 
standing crop sampling procedures for the Canadian high 
Arctic. Arctic Alpine Research 8: 139-150. 

Whittaker, R. H. 1975. Communities and ecosystems. 2nd 
edition. Macmillan Publishing Company, New York. 
385 pp. 

Wielgolaski, F. E. 1975. Productivity of tundra ecosys- 
tems. In National Academy of Sciences productivity of 
world ecosystems. United States National Academy of 
Sciences, Washington, D.C. pp. 1-12. 

Received 17 January 1977 
Accepted 21 October 1977 



Food Habits of Three Sympatric Species of Insectivora 
in Western Washington 



Carol J. Terry 

College of Forest Resources, University of Washington, Seattle, Washington 98195 

Present Address: Department of Systematics and Ecology and the Museum of Natural History, University of Kansas, 
Lawrence, Kansas 66045 



Terry, Carol J. 1978. Food habits of three sympatric species of Insectivora in western Washington. Canadian Field- 
Naturalist 92(1): 38-44. 

Sorex vagrans vagrans, S. trowbridgii trowbridgii, and Neurothchus gibbsi minor were maintained in captivity and fed seeds 
of various herb, shrub, and tree species. Invertebrates, carrion, and mushrooms were also provided. The only seed species 
rejected by all individuals tested was purple foxglove {Digitalis purpurea). Neurotrichus, the largest of the species studied, 
readily consumed all other food items offered. Sorex vagrans and S. trowbridgii were restricted to smaller food items, 
seemingly because of their inability to penetrate heavy seed coats and capsules, and thick exoskeletons. 

Key Words: Sorex. Neurotrichus, shrews, competition, sympatry, granivory. 



Several species of shrew {Sorex) and the shrew 
mole {Neurotrichus) are often collected in the 
same habitats in western Washington. Because 
these species are small, have high metabolic rates 
(Pearson 1948), and require large amounts of 
food to survive (Broadbooks 1939; Morrison 
et al. 1957; Buckner 1964), it seems likely that 
food may at times be limiting, resulting in 
interspecific competition. To examine potential 
competition for food among these species, I 
studied the food and feeding habits of sympatric 
Sorex trowbridgii trowbridgii, S. vagrans 
vagrans, and Neurotrichus gibbsi minor. Mean 
weight and standard error for the three species 
were respectively 5. 1 ± 0.22 g (n = 16), 
4.2±0T9g(n =18), 7.8 ± 0.45 g (n = 4). This 
investigation focused on the types of foods eaten 
and the size of food items. Due to the small body 
size of the animals, size of acceptable food items 
may be an important factor in influencing their 
diet and the intensity of interspecific compe- 
tition. Although shrews are considered to be 
primarily insectivorous (Jameson 1955; 
Williams 1955; Findley 1967) they also consume 
seeds (Ingles 1967; Criddle 1973) and may be 
major predators on seeds of Douglas fir 
{Pseudotsuga menziesii) and other conifers 
(Moore 1942; Gashwiler 1970). Since herb, 
shrub, and tree seeds are potentially numerous in 
western coniferous forests, it would seem 
advantageous for an animal with so high a 



metaboHc rate to take advantage of this energy 
source. 

Most food studies of Sorex consist of exami- 
nation of stomach contents (Whitaker and 
Mumford 1972; Rudge 1968). I have observed 
that captive shrews often remove the seed coat 
before ingesting the endosperm; thus stomach 
contents examination may not detect the 
presence of seeds, and previous studies may have 
underestimated the role of seeds in the diet of 
shrews. Moreover, examination of stomach 
contents gives only an indication of what the 
shrews had eaten very recently and what was 
immediately available to them. It is biased in 
favor of those foods that are less readily 
digestible and those that are seasonally avail- 
able. Therefore to obtain an indication of 
acceptable sizes and types of food items, I 
observed the feeding habits of several shrews and 
shrew moles in captivity. 

Methods 

In July 1972 five Sorex trowbridgii trow- 
bridgii, five 5*. vagrans vagrans, and two 
Neurotrichus gibbsi minor were captured live in 
buried half-gallon paint cans in a serai Douglas 
fir {Pseudotsuga menziesii) stand 32 km east of 
Issaquah, King County, Washington. Each 
animal was transferred to a 76-L aquarium 
containing 5 to 10 cm of humus, the surface of 
which was half covered with moss 



38 



1978 



TERRY: INSECTIVORA FOOD HABITS, WESTERN WASHINGTON 



39 



{Eurhynchium oreganum). The aquaria were 
kept indoors in an area not subject to any regular 
human or mechanical disturbance. Animals 
were maintained on a diet of millet and Tyrell's 
chicken dog food; during the first few days of 
captivity they were offered various insects and 
tree seeds in addition. 

Tree seeds for experimentation and accurate 
information on viability of seed lots were made 
available by the Washington State Department 
of Natural Resources. Herb and shrub seeds 
were gathered from the area in which the animals 
had been collected. I conducted three types of 
tree seed tests: encounter/ preference tests, 
hourly tests, and 12-h tests. Seeds were offered 
on aluminium pans, 10X15 cm, which had been 
taped to reduce vibrations and which the shrews 
had used previously as food containers. All food 
was removed from the cages at least one hour 
prior to the initiation of the encounter/ 
preference and hourly tests. 

Encounter I Preference 

The encounter/ preference test was designed 
to determine any immediate preference for 
different species of seeds. Animals were pre- 
sented with equal amounts of evenly spaced 
seeds: either four seeds of two species were 
alternated in a straight line or 10 seeds of two 
species were alternated in a 4-by-5 grid. No 
specific time interval was set because of vari- 
ability of activity patterns; instead, tests were 
terminated when there was a pause in the 
animal's activity and at least half of the seeds had 
been removed or eaten. 

Hourly Tests 

Both species of shrews exhibited hoarding 
behavior during early captivity, carrying seeds 
some distance from the seed pan and burying 
them in the moss or soil. Because of this, it was 
not possible to give the shrews large numbers of 
seeds and correlate the number removed or eaten 
with consumption or activity, for the shrews 
might remove large quantities of seeds when they 
were first presented and then eat them over an 
extended period of time. A partial solution to 
this problem was to give the shrews a small 
number of seeds over short periods of time. 
Therefore, for the hourly tests, 20 seeds of each 
of the two or three tree species being compared 
were given to the animals at hourly intervals. 



Tests lasted from 10 to 17 h and were conducted 
at different times during the day and night. In 
this way possible variations in consumption and 
activity rates during different periods of the day, 
and associated changes in preferences, could be 
detected. Supplemental food was not available 
to the animals during the hourly tests. 

Viajbility of individual seeds was unknown, so 
during the hourly tests uneaten seeds were 
replaced by seeds of the same species in order to 
reduce any error as a result of unacceptable 
seeds. If more than five seeds (25%) of any one 
species was removed by the animals during the 
hour, the remaining seeds of that species were 
discarded and 20 new seeds were given. If less 
than 25% of any one seed species had been 
removed, the number of seeds removed by the 
animal was replaced with new seeds. Therefore 
at the beginning of every hour 20 seeds of each 
tree species were available to each animal. 

12-h Tests 

The third type of seed test involved giving the 
animals a specific number of seeds of various 
tree species for 12-h intervals. This test elimi- 
nated any disturbance factor owing to changing 
seeds at hourly intervals and provided informa- 
tion on degree of preference: i.e., whether a 
certain seed species was eaten in smaller amounts 
during the hourly tests only because a more 
preferred species was present, but would be 
eaten readily if it were the only seed available. In 
order to reduce the risk of losing shrews through 
starvation or lack of some particular nutrient 
(Crowcroft 1951), measured amounts of dog 
food were present during these 12-h tests. 

No quantitative tests were made for herb and 
shrub seeds and fruits because only small 
amounts were available, and seed viability was 
uncertain. Fruits and seeds were offered at 
random, and the animals' behavior toward the 
item was recorded. For larger seeds (Lilium 
columbianum and Lupinus latifolius) lots of 
four or five were offered, while for the smaller 
seeds (Digitalis purpurea and Lamium 
purpureum) at least 20 were presented at one 
time. Dog food was always present during the 
herb and shrub seed tests. 

Insects, slugs, carrion, and mushrooms, as 
they became available, were also offered at 
random to the shrews. Dog food was not present 



40 



The Canadian Field-Naturalist 



Vol. 92 



Table 1 — Seeds removed during encounter/ preference tests 



Tree species pairs compared 



Species tested 



Number of replicates Seeds removed. 



Abies procera, 
Pinus monticola 

Pseudotsuga menziesii, 
Pinus monticola 

A bies procera, 
Pinus monticola 

Pseudotsuga menziesii, 
Pinus monticola 

Abies procera, 
Pinus monticola 

Pseudotsuga menziesii, 
Pinus monticola 



Sorex vagrans 
Sorex vagrans 
Sorex trowbridgii 
Sorex trowbridgii 
Neurotrichus gibbsi 
Neurotrichus gibbsi 



2 


14 




50 


2 


60 




90 


3 


83 




100 


5 


76 




80 


2 


38 




88 


1 


20 



30 



when animal matter was offered, but was 
available with the mushrooms. 

Results and Discussion 

Tree Seeds 
Short-term tests 

Throughout the food tests, responses of 
S. vagrans and 5". trowbridgii were similar. 
Neither species displayed a choice between seeds 
of Douglas fir {Pseudotsuga menziesii) and 
western white ^mt {Pinus monticola) or between 
Douglas fir and S'likdiS^vucQ {Picea sitchensis)'\n 
the encounter/ preference (Table 1) and hourly 
tests (Table 2). A definite preference was shown, 
however, for those three seed species relative to 
noble fir {Abies procera) and Pacific silver fir 
{A. amabilis) seeds. 

Thus results of these short-term tests indicate 
that true fir seeds were not eaten readily or at 
least were not preferred food, even though they 
are larger than the other seeds offered (Table 2); 
this may be associated with my observations that 
Abies seeds have a strong odor and that many 
are coated with resin. 

Hoarding behavior was exhibited by S. 
vagrans during the hourly tests and by S. 
trowbridgii during the encounter/ preference 
tests. Hoarding occurred in several individuals 
of both species and did not appear to be 
correlated with time of day or previous absence 
of food. On one occasion a Trowbridge Shrew 
removed and cached 67 sunflower seeds, offered 
in lots of 10, in 20 min. Although seed hoarding 
has not been reported in shrews and may be an 
artifact of captivity, hoarding of earthworms by 



5*. vagrans has been noted (Broadbooks 1939). 

Neurotrichus exhibited a definite preference 
for Sitka spruce, the smallest tree seeds available 
(Table 2). This marked preference of Neuro- 
trichus for the smallest seeds indicates that it is 
not restricted to larger food items, and may be an 
important competitor for seeds with the smaller 
shrews. 

Since hourly tests were conducted during 
different times of the day and night and lasted 
from 10 to 17 h, the numbers of seeds removed 
by the animals during each hour interval gave an 
indication of the activity and metabolic needs of 
the animals for a 24-h period. Results from these 
tests indicate that these animals are active at all 
times of day and have no long rest period. Ingles 
(1960) has also found that 5". vagrans obscurus is 
active except for brief naps. 

Long-term tests 

Sorex trowbridgii removed significantly fewer 
seeds (/*< 0.001) than S. vagrans during the 
hourly tests (Table 2), yet their seed consump- 
tion was similar for the 12-h tests (Table 3). 
Neurotrichus also removed fewer seeds during 
the hourly tests than during the long-term tests. 
These results indicate that the external dis- 
turbances of the hourly tests may have affected 
Neurotrichus and S. trowbridgii more than 
S. vagrans. 

The long-term tests also indicated that true fir 
seeds are an acceptable, though not preferred, 
food source for the shrews. Although signifi- 
cantly fewer Abies seeds were removed by 
S. trowbridgii and S. vagrans during the hourly 



1978 



TERRY: INSECTIVORA FOOD HABITS, WESTERN WASHINGTON 



41 



Table 2 — Preferences exhibited during hourly tree seed tests. Twenty seeds of each species were available to each animal at 
the beginning of every hour. Two animals were involved in each test. G-test expected frequencies for each group = total seeds 

eaten/number of tree species 





Average 


number of seeds 


removed 










per hour 




Number of 
replications 


Mean weight of a 

seed (N = 100) 

in mg 


Tree species compared 


Neurotrichus 
gibbsi 


Sorex 
trowbridgii 


Sorex 
vagrans 


Pseudotsuga menziesii, 
Picea sitchensis 


0.06 
12.16** 


5.39 
6.50 


10.05 
12.20 


54' 


13.25 
2.32 


Pseudotsuga menziesii, 
Picea sitchensis, 
Abies procera 


1.71 

7.00* 

0.18 


3.92 
5.38 
0.85 


5.01 
5.50 
1.90 


28 


13.25 

2.32 

38.10 


Pseudotsuga menziesii, 
Picea sitchensis, 
Abies amabilis 


1.33 

7.97** 

0.61 


3.66 
3.26 
0.53 


6.27 

7.89** 

0.33 


30 


13.25 

2.32 

35.35 


Pseudotsuga menziesii, 
Abies amabihs 


1.33 
0.61 


3.66 
0.53* 


6.27 
0.33** 


30 


13.25 
35.35 


Pseudotsuga menziesii, 
Abies procera 


1.71 
0.18 


3.92 
0.85* 


5.01 
1.90 


28 


13.25 
38.10 


Picea sitchensis, 
Abies amabilis 


7.97 
0.61** 


3.26 
0.53* 


7.89 
0.33** 


30 


2.32 
35.35 


Picea sitchensis, 
A bies procera 


7.00 
0.18** 


5.38 
0.85* 


5.50 
1.90 


28 


2.32 
38.10 


* P<0.05. 
**P<0.0\. 
' One Sorex trowbridgii, 


27 replications. 











tests (P< 0.005), no difference was shown 
between Abies and other tree seeds for the 
12-h tests iP>0.l). 

Herb and Shrub Seeds 

A summary of results with all herb and shrub 
species offered is given in Table 4. A 'Q' indicates 
that the seeds had been disturbed by the animal, 
but it is questionable whether any seeds were 



eaten. Shrews, and particularly Neurotrichus, 
commonly walked arounc} in the seed pan, eating 
some seeds, kicking others about, and def- 
ecating. Because of this behavior and the small 
size of some seeds, it was often possible to 
determine only that a few seeds had been eaten. 
There seems to be no relation between 
availability of these seeds to shrews and whether 
they were consumed. Many of the herb seeds 



Table 3 — Food removed by Sorex and Neurotrichus during the 12-h seed tests. Number of animals in each test is given 

in parentheses. A dash indicates that no test was made with that species. As Neurotrichus scattered proffered dog food 

about the cage, amounts for this animal were unobtainable 







Amount of food 


given 


Average 


amount of food 


remo\ 


'ed 


Foods compared 


S. vagrans (4) 


S. trowbridgii 


(4) 


A', gibbsi (2) 


Test#l 
















Pinus monticola 




20 seeds 




20.0 seeds 


20.0 seeds 




— 


Abies amabihs 




20 seeds 




14.0 seeds 


13.25 seeds 




— 


Pseudotsuga menziesii 


20 seeds 




19.75 seeds 


19.25 seeds 




— 


dog food 




ad lib. 




1.52 g 


2.16 g 




— 


Test #2 
















Pinus monticola 




50 seeds 




37.25 seeds 


50.00 seeds 




50.00 seeds 


Pseudotsuga men: 


ziesii 


50 seeds 




37.50 seeds 


50.00 seeds 




50.00 seeds 


dog food 




ad lib. 




0.60 g 


1.52 g 




unknown 



42 



The Canadian Field-Naturalist 



Vol. 92 



Table 4 — Qualitative results of herb, shrub, and mushroom experiments. Key: O = not eaten, Q = probably not eaten (see 
text), X = eaten. An asterisk in a column indicates that only one individual of that species was used in that particular seed test. 

A dash indicates no test was made with that species 



Food offered 



Sorex 
vagrans 



Sorex 
trowbridgii 



Neurotrichus 
gib b si 



Herbs 

Chrysanthemum leiicanihemum 

Cirsium sp. 

Digitalis purpurea 

Lamium purpureum 

Latuca saUgna 

Lilium columbianum 

Lupin us la t if alius 

Plant ago sp. 

Ranunculaceae (one species) 

Rumex obtusifolius 

Taraxacum officinale 
Shrubs 

Berberis nervosa 

Gaultheria shallon 

Rubus leucodermis 

Vaccinium parvifolium 
Mushrooms 

Agaricus hondensis 

Agaricus nivescens 

Boletus zelleri 

Cerosa sp. 

Helve I la lacunosa 

Hygrophorus subalpinus 

Laccaria laccata 

Lactarius deliciosa 

Russula brevipes 

Spropharia ambigua 



offered occur in disturbed areas such as road- 
sides and forest openings, and the forest species 
S. trowbridgii and Neurotrichus may have had 
no previous contact with them. Yet only one 
herb species, Digitalis purpurea, was avoided by 
all three species. This was also the smallest seed 
offered, so it is unknown whether it was rejected 
because of its size or its chemical nature. 

Vaccinium parvifolium was not eaten by 
S. vagrans. This plant is a common species in 
forests and forest edges, but it is possible that 
vagrans was unable to penetrate the outer skin of 
the fruit. This interpretation is supported by the 
fact that plump ripe berries of both Gaultheria 
shallon and Berberis nervosa were left un- 
touched whereas older shriveled ones were 
eaten. 

The ability of the shrews to bite into some 
berries, and to open seed cases may be a factor 
that limits their food supply. For instance, some 



Lactuca saligna fruits with enclosed seeds were 
offered and other seeds were removed and then 
presented. The free seeds were eaten rapidly by 
all three insectivores. Less than 20% of the fruit 
capsules were opened by the shrews, although all 
were opened by Neurotrichus. As with the tree 
seed experiments, those with herbs and shrubs 
suggest that these insectivores will eat almost 
any food they can handle. 

Mushrooms 

Table 4 also provides the results of the 
mushroom tests. This was a very Hmited sample 
and included only mushrooms known to be non- 
poisonous to humans. Neurotrichus readily ate 
all but one of the species of mushrooms offered, 
but the two shrews were more selective. Sorex 
trowbridgii ate substantial amounts of five 
species of mushrooms while 5". vagrans merely 
nibbled on them. 



1978 



TERRY: INSECTIVORA FOOD HABITS, WESTERN WASHINGTON 



43 



Animal Matter 

Although the shrews and the shrew moles 
readily ate the chicken dog food, they all 
preferred other live or dead animal matter. All of 
the captive animals ate earthworms; larval, 
pupal, and adult forms of mealworms; sowbugs; 
aphids; lepidopterous pupae; maggots and other 
insect larvae infesting a rotting mushroom 
(Armillaria mellea); as well as small slugs 
(Prophysaon andersoni and Arion ater) and slug 
eggs {Avion ater). 

Neurotrichus readily ate dead Deer Mice 
(Peromyscus maniculatus) and Rufous-sided 
Towhee (Pipilo erythrophthalmus), large slugs 
{Ariolimax columbianus), large black centi- 
pedes, and large beetles. One shrew mole failed 
to catch an active spider. Sorex vagrans ate 
termites, ants, spiders, and some carrion, but did 
not eat large black carabid beetles. Sorex 
trowbridgii ate termites, ants, small centipedes 
and millipedes, and an injured butterfly. 

Conclusions 

Studies of food habits indicate that these 
animals are generalists with regard to food. 
None of the animal matter offered to these 
animals was refused and Digitalis purpurea v^'ds 
the only seed that was definitely not eaten by any 
of the insectivores studied. In general, these 
animals ate a portion of all food items offered to 
them, even those with which they may have had 
no previous experience. Two species of tree 
seeds, Picea sitchensis and Pinus monticola were 
eaten in large quantities by all of the animals, 
even though these trees occur only sporadically 
in this vegetation zone (Franklin and Dyrness 
1973). The conclusion that these animals are 
food generalists corresponds with what is known 
about their metabolic requirements: a large 
amount of food relative to size is required and it 
would be selectively advantageous for them to 
eat anything that is available which provides 
sufficient nutrition or energy. 

This study indicates no distinct divisions 
between the species of insectivore and the sizes of 
acceptable food items. Neurotrichus, the largest 
animal studied, accepted and preferred the very 
small Picea sitchensis seeds. It was also capable 
of eating much larger food items, however, than 
were S. vagrans and 5". trowbridgii. Sorex 
vagrans experienced the most difficulty in 



handling larger food items and those with 
heavier seed coats or exoskeletons. Therefore 
larger food items are available to Neurotrichus 
which are either less available or unavailable to 
the shrews. 

No measure of the total amount of food 
available to these animals exists, so it is 
unknown whether food is a limiting factor to 
their growth and distribution. These food tests 
indicate, however, that there is a large overlap in 
acceptable food items of these shrews and 
shrew moles and suggests that competition for 
food may occur in areas where these animals 
coexist. 

Acknowledgments 

I thank R. D. Taber and K. O. Richter, 
University of Washington, for helpful sugges- 
tions throughout this study; and R. S. Hoffmann 
and J. W. Koeppl, University of Kansas, for 
critically reading the manuscript. The work 
reported in this paper was supported in part by 
National Science Foundation grant number 
Gb-36810X to the Coniferous Forest Biome, 
Ecosystem Analysis Studies, U.S./ International 
Biological Program. This is contribution num- 
ber 228 from the Coniferous Forest Biome. 



Literature Cited 

Broadbooks, H. E. 1939. Food habits of the vagrant shrew. 
Murrelet 20: 62-66. 

Buckner, C. H. 1964. Metabolism, food capacity, and 
feeding behavior in four species of shrews. Canadian 
Journal of Zoology 42: 259-279. 

Criddle, S. 1973. The granivorous habits of shrews. Cana- 
dian Field-Naturalist 87: 69-70. 

Crowcroft, P. 1951. Keeping British shrews in captivity. 
Journal of Mammalogy 32: 354-355. 

Findley, J. S. 1967. Insectivores and dermopterans. In 
recent mammals of the world. Edited by S. Anderson and 
J. K. Jones, Jr. Ronald Press Co., New York, pp. 87-108. 

Franklin, J. F. and C. T. Dyrness. 1973. Vegetation of 
Oregon and Washington. U.S.D.A. Forest Service Gen- 
eral Technical Report PNW-8. vii + 417 pp. 

Gashwiler, J.S. 1970. Further study of conifer seed sur- 
vival in a western Oregon clearcut. Ecology 51: 849-854. 

Ingles, L. G. I960. A quantitative study on the activity 
of the dusky shrew (Sorex vagrans obscurus). Ecology 
41: 656-660. 

Ingles, L. C. 1967. Mammals of the pacific states. Stanford 
University Press, Stanford, California, xii + 506 pp. 

Jameson, E. W., Jr. 1955. Observations on the biology of 
Sorex trowbridgii in the Sierra Nevada, California. 
Journal of Mammalogy 36: 339-345. 



44 



The Canadian Field-Naturalist 



Vol. 92 



Moore, A. W. 1942. Shrews as a check on Douglas fir 
reproduction. Journal of Mammalogy 23: 37-41. 

Morrison, P. R., M. Pierce, and F. A. Ryser. 1957. Food 
consumption and body weight in the masked and short- 
tailed shrews. American Midland Naturalist 57: 493-501. 

Pearson, O. P. 1948. Metabolism of small mammals, with 
remarks on the lower limit of mammalian size. Science 
(Washington. D.C.) 108: 44. 

Rudge, M. R. 1968. The food of the common shrew 
Sorex araneus L. (Insectivora: Soricidae) in Britain. 



Journal of Animal Ecology 37: 565-581. 
Whitaker, J. O., Jr. and R. E. Mumford. 1972. Food and 

ectoparasites of Indiana Shrews. Journal of Mammalogy 

53: 329-335. 
Williams, O. 1955. The food of mice and shrews in a 

Colorado montane forest. University of Colorado Studies, 

Biology Series, Number 3: 109-114. 

Received 19 May 1977 
Accepted 21 November 1977 



Nesting Behavior and Food Habits of 
Parasitic Jaegers at Anderson River Delta, 
Northwest Territories 

Marilyn Martin' and Thomas W. Barry^ 

'Macdonald College of McGill University, Ste. Anne de Bellevue, Quebec HOA ICO 
^Canadian Wildlife Service, Edmonton, Alberta T5J 1S6 

Martin, Marilyn and Thomas W. Barry. 1978. Nesting behavior and food habits of Parasitic Jaegers at Anderson River 
delta, Northwest Territories. Canadian Field-Naturalist 92(1): 45-50. 

Based on the seven nests located at Anderson River delta in 1973, Parasitic Jaegers (Stercorarius parasiticus) had a breeding 
density of 1 pair per 2300 ha. Breeding success was 14.3%. Males and females shared incubation. A chick at one nest was 
unattended by an adult only 8% of the time. Defended core areas were within a 300-m radius of the nest, although hunting 
areas extended at least 3 km. Bird remains, particularly passerines, were found in 85.0% of the pellets collected. Mammals, 
mainly microtine rodents, were in 25.4% of the pellets. Other food included eggs, insects, and berries. 



Parasitic Jaegers {Stercorarius parasiticus) 
have a breeding range in North America that in 
part overlaps with that of Pomarine {S. 
pomarinus) and Long-tailed Jaegers {S. longi- 
caudus). Pitelka et al. (1955) and Maher (1974) 
have studied the ecology of these three species of 
jaegers in Alaska where they are sympatric. The 
Parasitic Jaeger was the only species of jaeger 
breeding in the Anderson River delta. North- 
west Territories (69°42'N, 129°00'W). The other 
species occurred only as migrants (MacFarlane 
1891; Hohn 1959; Barry 1967). We studied 
nesting Parasitic Jaegers in this area where they 
were free from interactions with other jaeger 
species. This paper reports their nesting be- 
havior and food habits in 1973 at the Anderson 
River delta. 

Study Area and Methods 

The study area is shown by the delta boundary 
in Figure 1. A detailed description of the 
physical features and vegetation of the delta is 
given by Barry (1967). Parasitic Jaegers and 
Glaucous Gulls (Larus hyperboreus) are the 
principal avian predators in the delta. There are 
nesting colonies of Lesser Snow Geese {Chen 
caerulescens caerulescens) and Black Brant 
{Branta bernicula nigricans) and scattered nests 
of other birds throughout the area. 

In 1973 we searched the 16 300-ha delta, by 
boat and on foot for nesting jaegers, which make 
themselves conspicuous by their characteristic 
defence display when their nests are approached. 



Nests were located and visited regularly to 
record their nesting chronology. We bow- 
trapped three adults while they were incubating 
and color-marked them with spray paint to 
enable us to make observations on their hunting 
areas. We built an observation tower near nest 1 
(Figure 1), from which we recorded data on 
incubation, chick care, defensive behavior, and 
hunting habits. 

Additional observations were made of jaegers 
hunting over the nearby goose colony. Re- 
gurgitated pellets and loose food items were 
collected from the core areas of nesting pairs. 
Individual food items were identified to species 
when possible. 

Additional field observations of Parasitic 
Jaegers from other years are included where 
applicable. 

Results and Discussion 

Breeding Biology 

The first Parasitic Jaeger arrived at the 
Anderson River delta between 25 May and 1 
June from 1953 to 1972. The first arrivals in 1973 
and 1974 were on 27 May. The estimated 
maximum pre-laying period for the pair that laid 
first was only 7 days. This supports Maher's 
(1974) conclusion that for arctic nesting 
Parasitic Jaegers, the pre-laying stage is much 
shorter than the 3 weeks Perry (1948) reported 
for jaegers in Britain. 

The chronology for each of seven nests located 
is given in Table 1. At each nest only a few days 



45 



46 



The Canadian Field-Naturalist 



Vol. 92 



69''42'n 




4 kilometers 



Figure 1. Location of Parasitic Jaeger nests and hunting area of pair 1 at Anderson Ri\er delta in 1973. 



after the eggs had hatched, the younger chick 
could not be found. Nesting success, involving 
two chicks fledging from 14 eggs, was 14.3%. 
Both predation and differential chick mortality 
contributed to the poor breeding success in 1973. 
Both chicks that fledged were still present in the 
core area and were accompanied by an adult on 
10 August. The chicks moved away from the nest 
within a day or two of hatching so that growth 
data was difficult to collect; however, one chick 
weighed 400 g at fledging and the other 425 g. 
Their ability to fly improved rapidly. On several 
occasions they were seen chasing their parents. 



The nesting density of jaegers at Anderson 
River in 1973, using the total area of the delta, 
was 1 pair per 2300 ha. This was similar to the 
low breeding densities found elsewhere by 
Maher (1974) and Taylor (1974). In 1973 we 
observed a maximum of 10 jaegers whose nests 
we failed to find or which were pre-breeders, 
non-breeders, or failed breeders. The numbers of 
these birds can vary greatly as in 1959, when 
50-60 non-nesting jaegers fed over the goose 
colonies. Taylor (1974) reported relatively 
constant numbers of non-breeders each year on 
Bathurst Island where there were few geese. In 



1978 



Martin and Barry; Parasitic Jaegers, Anderson River, N.W.T. 



47 



Table I — Nesting chronology for Parasitic Jaegers at Anderson River, Northwest Territories in 1973 



Nest 



Clutch 

size 



Date of laying of 
first egg 



Hatching 
date 



Fledging 
date 



June 8* 


Julys 


Taken by a wolf 


— 


Infertile or 




"embryonic death" 




June 9* 


July 6 


June 3* 


June 30 


)i sap pea red before 




hatching 


— 


June 7* 


July 4 



Disappeared July 20 



August 4 
July 29 



Disappeared July 15 



*Date estimated from hatching (accurate to 1 or 2 days). 

1974 three jaeger pairs occupied the same areas 
but no nests were found. In 1974 arctic-breeding 
species generally had poor success because of 
bad weather. 

The distances between the nest sites ranged 
from 900 to 7200 m as measured from aerial 
photos. Inter-nest distances varied widely and 
the sites were distributed unequally over the area 
(Figure 1). Nests 1, 2, 3, and 4 were con- 
centrated in or near the goose colony. Similarly, 
Angstadt (1961) reported Parasitic Jaegers 
nesting on the periphery of a Blue Goose colony 
at McConnell River, Northwest Territories. 

The distances between nests do not appear to 
reflect the defended area of Parasitic Jaegers. 
Breeding jaegers defended only a small area 
around their nests. Pair 1 defended a core area 
with a radius of about 1 80 to 300 m around their 
nest. The core area defended by other pairs 
appeared to be approximately the same size. 
Maher (1974), at Cape Sabine, found that pairs 
defended a core area with a radius of 183 to 
275 m from the nest. He also observed territorial 
displays away from the core area; we did not see 
these displays. We observed other jaegers 
hunting without interference outside the core 
area and found that one member of a nesting 
pair often joined a hunting party when it passed 
near its core area. Breeding pairs did not 
challenge strange jaegers except at the core and 
even then jaegers were allowed closer than other 
avian species. 

The known hunting area of pair 1 is shown in 
Figure 1 . They were seen at least 3 km from their 
nest and may have travelled farther but they were 
no longer visible to us beyond 3 km. When there 
was a disturbance on the core area the hunting 



bird of pair 1, if it was nearby, would return to 
join in the defense. Often only one bird was 
present during our visits to other nests, sug- 
gesting that members of these pairs were also 
foraging at some distance from the core area. 
Parmalee et al. (1967) and Taylor (1974) note 
that Parasitic Jaegers defend a relatively small 
area during the breeding season and do their 
hunting at some distance from the core area. 

Nesting Behavior 

During 40 h of observation of pair 1 between 
30 June and 4 July 1973, the color-marked 
parent incubated the nest 55% of the time. Its 
mate performed 45% of the incubation, indi- 
cating that parent birds share incubation duties 
about equally. The period of attentiveness varied 
from 15 to 1 10 min but usually lasted at least 1 h. 
Incubation periods of shorter duration were 
usually the result of interruptions by intruders 
(e.g., other jaegers, gulls. Golden Eagles {Aquila 
chrysaetos)). 

Normally the relieving bird glided toward the 
nest, and the incubating parent flew up seconds 
before its mate landed. It is possible that they 
vocalized during this period to achieve syn- 
chronization. 

Pair 1 was observed, after their eggs had 
hatched, for a total of 21 h between 6 and 19 
July. The color-marked parent remained in the 
core area 92% of the time. The other adult was 
present in the core area 38% of the time. The 
chick was alone only 8% of the time. At the other 
jaeger nests visited, the chick was never found 
alone even 12 days after fledging and was always 
found attended by the same adult, contrasting 
with Maher's (1974) findings that chicks were 



48 



The Canadian Field-Naturalist 



Vol. 92 



alone 50% of the time. 

During the incubation period, both aduhs of 
pair 1 hunted when they were not incubating. 
They did not share food until the day the first 
chick hatched. The color-marked bird begged 
from its mate, who regurgitated food. Sub- 
sequent to this, regurgitation was seen fre- 
quently. At other times the pair was observed to 
cooperate in pulling prey apart, with both taking 
a share. The color-marked parent sometimes left 
the core area to assist its mate in hunting or with 
an already initiated chase. 

Aggressive behavior and the distraction 
display were strongly developed at the onset of 
incubation. As a human approached the core 
area the birds stood alert. Within 75-100 m of 
the nest the birds usually began their distraction 
display which consisted of vigorous wing- 
flapping, jumping, and loud whimpering. They 
performed on the ground and also in nearby 
ponds. As the human reached approximately 
20-30 m from the nest an aggressive attack 
began. The bird generally flew in low from 
behind the intruder and frequently hit him with 
its wings and feet while it was in flight. There was 
much individual variation in these perform- 
ances. The color-marked adult of pair 1 was 
always the more aggressive of the two, initiating 
most displays and continuing them longer. The 
other two color-marked jaegers were also more 
aggressive than their mates. This indicates there 
are differences in defensive behavior between 
individuals of a pair. Some pairs were more 
aggressive than others in the intensity and length 
of display. The amount of aggression decreased 
with the number of our visits. 

Parasitic Jaegers also showed aggression 
toward Arctic Terns {Sterna paradisaea). Black 
Brant, Glaucous Gulls, Golden Eagles, other 
Parasitic Jaegers, Common Ravens {Corvus 
corax). Whistling Swans (Olor columbianus). 
Barren-ground Caribou {Rangifer tarandus), 
dogs {Canis familiaris), and a float plane. 

Food Habits 

Prey items in 173 food pellets were identified 
during the study (Table 2). Bird remains 
occurred in 85.0% of the pellets; remains of 
mammals appeared in 25.4%. Passerines ac- 
counted for 81.4% of the identified bird remains 
and the other 18.6% were from shorebirds. 



Muskrat remains were all collected from one 
territory and were probably scavenged. Insect 
remains and berry skins and seeds always 
occurred in small amounts. Eggshells occurred 
in 15.6% of the pellets, most often in trace 
amounts. Grass was usually present in small 
amounts, probably picked up accidentally. 

A large number of different food items were 
found among the loose food collected with the 
jaeger pellets. This material included eggs of 
ducks, geese, loons, and curlews; and the 
carcasses of an adult ptarmigan (Lagopus sp.), a 
young duck, and a small pike (Esox sp.). 
Parasitic Jaegers were also seen feeding on the 
eggs of Snow Geese, Black Brant, White-fronted 
Geese {Anser albifrons), Glaucous Gulls, Whis- 
tling Swans, Willow Ptarmigans (Lagopus 
lagopus), Lapland Longspurs {Calcarius lap- 
ponicus), and various ducks. 

Quantities of blueberries (Vaccinium uligi- 
(nosum), cloud-berries (Rubus chamaemorus), 
and cro wherries {Empetrum nigrum) grew 
around nest 5. As these ripened, more and more 
droppings appeared that were composed of 
berry seeds and skins. No other nests had 
droppings containing berries, but no other 
jaegers had large berry patches within their 
territories. 

Many authors have reported Parasitic Jaegers 
as predators on birds (Sutton 1932; Clarke 1940; 
Angstadt 1961; Parmalee et al. 1967; Taylor 
1974). The results of this study clearly indicate 
that birds, especially passerines, are a major 
food item, with microtine rodents being much 
less important. Maher (1974) found in Alaska 
that birds made up 82% of food items, with 
passerines predominating. 

Jaegers can eat eggs without ingesting much of 
the shell, so eggs may be a more important food 
item for nesting jaegers than our analysis of 
pellets indicates. Many birds had already started 
nesting when jaegers arrived in the spring. Geese 
lay one egg a day for several days before 
incubation begins and are off their nests for 
considerable periods. Hunting jaegers were 
frequently seen at goose nests during this period. 
Opportunities for nest predation decreased 
when geese began incubation. Jaegers then 
depended on accidental disturbances in the 
goose colony. In 1973 we did not see jaegers 
trying to drive geese from their nests, although 



1978 



Martin and Barry: Parasitic Jaegers, Anderson River, N.W.T. 



49 



Table 2— Frequency (%) of food items in 173 pellets of Parasitic Jaegers, Anderson River delta. Northwest 

Territories, 1973 



Food items 



Frequency 

(%) 



Bird remains (total) 
Charadriiformes 

Long-billed Dowitcher (Limnodromus scolopaceus) 

Semipalmated Sandpiper (Ereunetes pusillus) 
Passeriformes 

Horned Lark {Eremophila alpestris) 

Water Pipit (Anthus spinoletta) 

Redpoll (Acanthis spp.) 

Savannah Sparrow (Passerculus sandwichensis) 

Tree Sparrow (Spizella arborea) 

White-crowned Sparrow (Zonotrichia leucophrys) 

Lapland Longspur (Calcarius lapponicus) 
Unidentified bird remains 

Eggshell 

Mammal remains (total) 
Insectivora 

Shrew {Sorex arcticus) 
Rodentia 

Red-backed Vole (Clelhrionomys gapperi) 

Meadow Vole (Microtus oeconomus) 

Muskrat {Ondatra zibethicus) 

Lemming {Lemmus spp.) 

Collared Lemming {Dicrostonyx spp.) 
Carnivora 

Weasel (Mustela spp.) 
Unidentified mammal remains 

Fish remains 

Insect remains 

Berries 

Grasses 



85.0 

9.8 

.6 

4.6 

42.8 
1.7 
1.2 
.6 
5.2 
1.2 
3.5 
2.3 

32.4 

15.6 

25.4 

.6 

.6 

22.8 

1.7 

6.9 

5.8 

4.6 

4.0 

.6 

.6 

1.2 

.6 

18.5 

14.5 

32.4 



Barry (1967) has seen this. Angstadt (1961) 
reported groups of jaegers harassing incubating 
geese, with little success. 

Most hunting jaegers occurred in groups of 
one to three with a maximum of five. During the 
period when geese were incubating, groups of 
jaegers were frequently observed flying low over 
the colony. Jaegers were often seen rummaging 
in goose nests for eggs or abandoned goslings 
during and several days after the goose hatch. 
One hill was crowded with 175 Snow Goose 
nests and a great number of eggs was seen 
outside the nests. Jaegers were unable to 
scavenge these eggs until the geese moved out of 
the area. 

Parasitic Jaegers appeared promptly in the 
goose colony whenever a disturbance arose such 
as the passing of a helicopter or a Golden Eagle. 



Territorial fights among these geese provided 
jaegers with opportunities to prey on eggs. Barry 
(1967) found that visits to the goose colonies by 
Grizzy Bears ( Ursus arctos). Red Foxes ( Vulpes 
vulpes), and Arctic Foxes (Alopex lagopus) gave 
many opportunities for jaegers to feed on eggs. 
The mammals, feeding on eggs in one nest after 
another, frightened geese in their path, leaving 
the nests easy prey for jaegers. The same was true 
with human disturbances; jaegers would follow 
the field worker as he moved through the colony. 
After the goose hatch was complete we often 
saw pair I chasing small birds, which they 
usually successfully caught. One bird often 
initiated a pursuit and was joined by the other. 
Sometimes the prey alighted in the grass; then, 
while one jaeger hovered, the other stalked the 
victim on the ground. If the prey flew away. 



50 



The Canadian Field-Naturalist 



Vol. 92 



aerial pursuit began again. Pair I frequently 
walked through the grasses in their territory, and 
were likely catching insects. 

During the 1973 study we witnessed a few 
incidents in which jaegers parasitized other 
species within their hunting range. On three 
occasions in the goose colony jaegers took food 
from Glaucous Gulls, but twice we saw gulls 
successfully pirate food from jaegers. Twice 
jaegers unsuccessfully attempted to steal fish 
from Arctic Loons {Gavia arctica) in flight and 
twice we saw them chasing Arctic Terns 
presumably for the same purpose. All these 
incidents involved adult jaegers. A chick that 
had fledged only 10 days earlier was seen 
attacking an Arctic Tern carrying a fish. 

Literature Cited 

Angstadt, R. B. 196L Predation by jaegers in a Blue 

Goose colony. M.Sc. thesis, Cornell University, Ithaca, 

New York. 49 pp. 
Barry, T. W. 1967. The geese of the Anderson River delta, 

N.W.T. Ph.D. thesis. University of Alberta, Edmonton. 

212 pp. 
Clarke, C. H. D. 1940. A biological investigation of the 

Thelon Game Sanctuary. National Museum of Canada 



Bulletin 96. 135 pp. 
Hohn, E. O. 1959. Birds of the mouth of the Anderson 

River and Liverpool Bay, Northwest Territories. 

Canadian Field-Naturalist 73(2): 93-1 16. 
MacFarlane, R. 1891. Notes on and list of birds and 

eggs collected in Arctic North America, 1861-1866. 

Proceedings of the United States National Museum, 

Washington, D.C. 14(865): 413-446. 
Maher, W. J. 1974. Ecology of Pomarine, Parasitic and 

Long-tailed Jaegers in northern Alaska. Pacific Coast 

Avifauna Number 37. 148 pp. 
Parmalee, D. F., N. A. Stephens, and R. H. Schmidt. 1967. 

The birds of southeastern Victoria Island and adjacent 

small islands. National Museum of Canada Bulletin 

Number 222. 229 pp. 
Fitelka, F. A., P. Q. Tomich, and G. W. Treichel. 1955. 

Ecological relations of jaegers and owls as lemming 

predators near Barrow, Alaska. Ecological Monographs 

25(3): 85-117. 
Perry, R. E. 1948. Shetland Sanctuary. Faber and Faber, 

London. 300 pp. 
Sutton, G. M. 1932. The birds of Southampton Island. 

Memoirs of the Carnegie Museum 12(2): 1-275. 
Taylor, P. S. 1974. Summer population and food ecology 

of jaegers and Snowy Owls on Bathurst Island, N.W.T., 

emphasizing the Long-tailed Jaeger. M.Sc. thesis. Uni- 
versity of Alberta, Edmonton. 168 pp. 

Received 14 December 1976 
Accepted 29 October 1977 



Reproductive Success of Herring Gulls 

on Granite Island, Northern Lake Superior, 

1975 and 1976 

John P. Ryder and Timothy R. Carroll 



Department of Biology, Lakehead University, Thunder Bay, Ontario P7B 5E1 

Ryder, J. P. and T. R. Carroll. 1978. Reproductive success of Herring Gulls on Granite Island, northern Lake Superior, 
1975 and 1976. Canadian Field-Naturalist 92(1): 51-54. 

The reproductive success of 200 pairs of Herring Gulls (Larus argentatus) that nested on Granite Island, northern Lake 
Superior in 1975 and 1976 is reported. The proportion of nests which hatched at least one egg was 96% in 1975 and 97% in 
1976. Hatching success was 79.6% and 84.2% respectively. Disappearance and embryo failure were the main causes of egg 
mortality, 15.8% in 1975 and 12.4% in 1976. The number of fledged young per pair of nesting adults was calculated at 1.32 in 
1975 and 1 .55 in 1976. Examination of organochlorine and mercury residues in eggs showed generally that levels were below 
those recorded from Lakes Ontario and Michigan and above those from Lakes Huron and Erie. Based on this and concurrent 
studies on the Great Lakes Herring Gull population, no general relationship has been estabhshed between organochlorine 
residues and reproductive success in all Great Lakes populations of the Herring Gull. 

Key Words: Herring Gull, reproductive success, pollution. Lake Superior. 



Recently a number of papers have sum- 
marized the reproductive performance of Her- 
ring Gulls {Larus argentatus) that nest within the 
Canadian Great Lakes ecosystem (Gilbertson 
1974; Gilbertson and Hale 1974a, b; Morris and 
Haymes 1977; Teeple 1977). The above authors 
have reported relatively low reproductive suc- 
cess compared to those of studies of eastern 
seaboard colonies (Kadlec and Drury 1968; 
Haycock and Threlfall 1975) and European 
colonies (Harris 1964; Parsons 1971). Much of 
the reproductive failure of the lower Great 
Lakes Herring Gulls was caused by high 
early embryonic death (Gilbertson and Hale 
1974a), the disappearance of eggs, and poor 
survival of chicks (Gilmanetal. 1977). Although 
the actual cause of the lower Great Lakes phenom- 
enon is still enigmatic it has been associated with 
heavy contamination of eggs and tissues of adult 
birds with organochlorines, specifically DDE and 
polychlorinated biphenyls (PCBs). 

Stimulated by the reports of poor repro- 
ductive success of Herring Gulls in the lower 
Great Lakes in 1973 (Gilbertson and Hale 
1974b), we initiated a 2-year study of the nesting 
biology of the species at a colony in northern 
Lake Superior. This report represents the first 
documentation of the reproductive performance 
of the gulls over a two-season period from a 
northern Great Lakes region and serves as a 
means of comparison with current data from 
other colonies. 



Study Area and Methods 

The study was conducted on Granite Island 
(48°43'N, 88°29'W), a rock outcrop about 
400 m by 200 m and 4.8 km from the closest 
mainland point northeast of Sibley Peninsula 
(see Ryder 1974, Figure 1). The island is a 
strongly undulating rock surface about 30 m 
above the surrounding waters of Black Bay. 
Over half the island is forested by Balsam Fir 
{Abies balsamea). White Cedar {Thuja occi- 
dentalis), and White Birch {Betula papyrifera). 
Approximately 150 pairs of Herring Gulls nest 
in the shrub and bare rock areas of the northwest 
part of the island. The east part of the island is 
used for nesting by about 1000 pairs of Ring- 
billed Gulls (L. delawarensis). There is virtually 
no overlap in the nesting area of the two species, 
although 5-10 pairs of Herring Gulls nested on 
the northwest and west borders of the Ring- 
billed Gull colony. The only mammals seen 
during our studies on Granite Island were 
Snowshoe Hares {Lepus americanus) and Red- 
backed Voles {Clethrionomys gapperi). 

In 1975 and 1976 ice prevented us from 
visiting Granite Island before 13 May and 11 
May respectively. On our initial visits, we 
marked the eggs in 100 Herring Gull nests with 
non-toxic felt marker pens. The remaining nests 
were either in dangerous locations (close to 
slippery rocks near deep water) or adjacent to 
the Ring-billed Gull colony where experimental 
studies were underway. Each nest was marked 



51 



52 



The Canadian Field-Naturalist 



Vol. 92 



by placing a numbered plastic strip, 50 cm long, 
either under the nest or securing it to a nearby 
bush or tree. We visited each nest two or three 
times a week to compile nest histories. We did 
not visit the colony during periods of excessive 
heat or cold as we assumed disturbances during 
such conditions would be detrimental to the eggs 
and/ or young (see Nisbet 1975; Vermeer 1970). 
We web-tagged each newly-hatched chick with a 
numbered fingerling fish tag. We later banded 
each chick with an aluminum United States Fish 
and Wildlife Service leg band. 

We collected 19 eggs in 1974 and 20 eggs in 
1975 from three-egg clutches which were not 
part of our nesting studies. These eggs were used 
to determine the levels of organochlorine, 
polychlorinated biphenyls (PCBs), and mercury. 
Analyses were conducted by the Ontario 
Research Foundation (cf., Reynolds 1969). 

We define terms used in this paper as follows: 
hatching success, the proportion of eggs laid 
which hatched; reproductive success, the num- 
ber of chicks that survived to 21 days per pair of 
reproducing adults. Although a number of 
authors have used different ages of chicks to 
measure post-hatching survival of Herring Gulls 
(40-45 days, Keith 1966; 30 days, Morris and 
Haymes 1977; 15 days, Drury and Kadlec 1974; 
Nisbet and Drury 1972; 7 days, Parsons 1970) we 
used 21 days for fledging because, according to 
authors cited in and including Kadlec and Drury 
(1968), major mortality of Herring Gull chicks 
occurs during the first three weeks. Hunt (1972) 
considered young Herring Gulls to have sur- 
vived the prefledging stage if they weighed 500 g. 
Data presented by Harris (1964) show that, 
depending on brood size, chicks reach this 
weight in about 20-24 days after hatching. 



Results 

In both years egg-laying was underway by the 
time we first visited Granite Island. The data in 
Table 1 are based on backdating 28 days when 
necessary from the dates eggs hatched (Haycock 
and Threlfall 1975). Approximately 80% of the 
nest sites used in 1975 were occupied in 1976. 
Seventy-five percent of the nests were located on 
sites adjacent to or on a vegetation substrate. 
The remainder were isolated from any vege- 
tation (see Brown 1967). 

The average clutch size was 2.99 ±0.17 (so) 
in 1975 and 2.98 ± 0.17 in 1976. Except for two 
2-egg clutches in both years and one 4-egg clutch 
in 1975, all nests contained three eggs. Based on 
data presented in Gilman et al. (1977), the 1975 
distribution from Granite Island differs sig- 
nificantly {P < 0.05) (larger) from those col- 
lected from Lakes Huron, Erie, and Ontario in 
that year. No comparable data are yet available 
for 1976 from these same locations. The Herring 
Gulls on Granite Island laid no single-egg 
clutches and renesting was virtually nonex- 
istent during the study period. 

Table 1 shows there was little relation between 
time of egg-laying and hatching success. In each 
year over 50% of the clutches hatched in a 5-day 
period, indicating a high degree of synchrony. In 
1975, 96% of the nests hatched one or more eggs 
and in 1976, 97% of the nests were successful. 
Hatching success in the 2 years was 79.6% and 
84.2% respectively. The high success of the 2 1 -25 
May in 1975 and 1976 and 28-30 April nesters in 
1 976 is most likely an artifact of the small sample 
size. 

The fate of unhatched eggs is given in Table 2. 
Disappearance and embryo failure were the 
principal causes of egg mortality, although 



Table I — Egg-laying frequency and hatching success of Herring Gulls on Granite Island, 1975 and 1976 



Date 
laid 



Nurr 


iber of 
laidi 


eggs 


Perce 


nt hatched 


1975 




1976 


1975 


1976 






12 




lOO.O 


— 




94 


— 


89.4 


39 




142 


79.5 


81.0 


168 




35 


83.9 


94.3 


78 




7 


80.8 


71.4 


3 




2 


100.0 


lOO.O 



28-30 April 
1-5 May 
6-10 May 
II-I5 May 
16-20 May 
21-25 May 



'The total differs from 299 eggs laid in 1975 (Table 2) because all eggs in four nests ( 1 1 eggs) did not hatch so that laying dates could not be calculated by back dating; 
similarly the 1976 total differs from 298 eggs laid because all eggs in two nests (6 eggs) did not hatch. 



1978 



Ryder and Carroll: Herring Gull Reproduction. Lake Superior 



53 



Table 2- 



-Fate of unhatched Herring Gull eggs on Granite 
Island. 1975 and 1976 





1975 


1976 


Number of eggs laid 


299 


298 


Hatched 


238 (79.6)1 


251 (84.2) 


Failed to hatch 


61 (20.4) 


47(15.8) 


Disappeared 


19 (6.4) 


19 (6.4) 


Embryo failure 


28 (9.4) 


18 (6.0) 


Pipped and died 


5(1.7) 


3(1.0) 


Cracked shell 


4(1.3) 


5(1.7) 


Outside nest 


5(1.7) 


2 (0.7) 



'Numbers in parentheses are percentages of the total number of eggs laid. 

embryo failure values were below those given by 
Oilman et al. (1977) for Lake Erie (16.7%) and 
Lake Ontario (35.1%), and Gilbertsonand Hale 
(1974a, b) for Lake Ontario (20% and 22% 
respectively). Our data correspond closely in 
these two mortality categories with those of 
Haycock and Threlfall's (1975) Newfoundland 
study (6%). 

Approximately two-thirds of the chicks we 
found dead each year succumbed before they 
reached 10 days of age. These findings are 
similar to the results reported byPaynter(1949), 
Harris (1964), Brown (1967), Kadlec and Drury 
(1968), and Hunt and Hunt (1976). We classified 
mortality as outUned in Table 3. Birds that were 
eaten in whole or in part we considered 
cannibahzed, because several cases of this were 
observed, and no active avian or mammalian 
predators were seen on the island during the 
study. Head injuries are associated with ter- 
ritorial defense by adults when chicks wander 
onto their territories (Haycock and Threlfall 
1 975). Chicks found dead for no apparent reason 
are enigmatic. Although we cannot dismiss the 
possibility that these chicks may have died from 
disease, it would be misleading to associate these 
deaths to such a cause without additional data. 



Teeple (1977) found cloacal fecal impaction, 
diarrhoea, and malnutrition in dead chicks from 
Brothers Island, Lake Ontario, in 1973, but 
stated that autopsies gave no indication what 
caused these conditions. Chicks that we found 
dead in or close to their nests after heavy storms 
or rain were considered to have died of exposure. 

The number of chicks calculated to have 
fledged per nesting pair was 1 .32 in 1 975 and 1 .55 
in 1976. These figures are based on our repeated 
sightings of live chicks to 21 days of age and on 
assumptions regarding the fate of the dis- 
appeared chicks. For the latter, we have 
assumed, based on our findings of dead, banded, 
known-age chicks, that two-thirds of the chicks 
that disappeared before they were 10 days old, 
were likely dead. Similarly, we have assumed 
that one-third of the chicks that were not 
relocated after they were 10 days old, had died. 

The validity of the above assumptions is 
difficult to measure and remains open to 
discussion of post-hatching mortality patterns 
and fledging times of Herring Gulls. In that our 
searches for chicks on Granite Island were 
frequent and thorough, we are confident our 
calculated reproductive success closely depicts 
the actual survival of chicks. Values given for 
reproductive success at other Great Lakes 
locations (Morris and Haymes 1977; Teeple 
1977) are all below the Lake Superior levels. 

The data on organochlorine and mercury 
levels from all the Great Lakes Herring Gull 
samples from 1974 and 1975 have recently been 
reported in detail by Oilman et al. (1977). The 
general pattern of contamination with organo- 
chlorines puts Lake Superior intermediate 
between higher levels in Lakes Ontario and 
Michigan and lower levels in Lakes Huron and 
Erie (Oilman et al. 1977). Mercury residues 
recorded in 1974 and 1975 are similar to those 



Table 3 — Mortality of Herring Gull chicks on Granite Island, 1975 and 1976 



Number of dead chicks 



Cause of death 



Percent of total 
number of deaths 



1975 


1976 


1975 


1976 


7 


7 


14.3 


17.9 


5 


14 


10.2 


35.9 


32 


14 


65.3 


35.9 


5 


4 


10.2 


10.3 



Cannibalism 
Head injury 
No visible injury 
Exposure 



54 



The Canadian Field-Naturalist 



Vol. 92 



reported by Ryder (1974) and likely below toxic 
levels. 

Discussion 

The results of this study show that, compared 
to other Great Lakes colonies, the Granite Island 
Herring Gulls show a hatching success equiv- 
alent to or higher than those reported from 
colonies outside the Great Lakes ecosystem (see 
Morris and Haymes 1977). The high degree of 
synchrony of egg-laying and hatching coupled 
with the almost ubiquitous three-egg clutches on 
Granite Island have virtually eliminated wide 
variation which markedly affects reproductive 
success. 

The task of determining why differences occur 
in the reproductive success amongst colonies in a 
large single ecosystem is difficult. This investiga- 
tion and others referred to have only noted 
annual productivity via the best methods 
available. Factors such as colony stability, 
habitat safety (security from flooding and poor 
drainage), age, experience, pairbond charac- 
teristics, and many other factors all remain 
virtual unknowns in the large study area under 
review. To date, no agreement has been reached 
which links definitively environmental toxicants 
and reproductive success in this species in all its 
Great Lakes environments (see Morris and 
Haymes 1977, p. 805; Teeple 1977, p. 156). 

Acknowledgments 

Financial support for this and related studies 
on Granite Island was received from Environ- 
ment Canada, Canadian Wildlife Service, Toxic 
Chemicals Division, and the National Research 
Council of Canada (grant A6520 to J. P. Ryder). 
We thank L. Somppi and D. Barnes for field 
assistance and R. Trowbridge for allowing us to 
base our operations at Bonavista. 

Literature Cited 

Brown, R. G. B. 1967. Species isolation between the Her- 
ring Gull LMrus argentatus and Lesser Black-backed 

Gull L.fuscus. Ibis 109: 310-317. 
Drury, W. H.and J. A. Kadlec. 1974. The current status of 

the Herring Gull population in the northeastern United 

States. Bird-Banding 45: 297-306. 
Gilbertson, M. 1974. Pollutants in breeding Herring Gulls 

in the lower Great Lakes. Canadian Field-Naturalist 

88: 273-280. 
Gilbertson, M. and R. Hale. 1974a. Early embryonic 

mortality in a Herring Gull colony in Lake Ontario. 



Canadian Field-Naturalist 88: 354-356. 
Gilbertson, M. and R. Hale. 1974b. Characteristics of the 

breeding failure of a colony of Herring Gulls on Lake 

Ontario. Canadian Field-Naturalist 88: 356-358. 
Gilman, A. P., G. A. Fox, D. B. Peakall, S. M. Teeple, 

T. R. Carroll, and G. T. Haymes. 1977. Reproductive 

success and egg organochlorine and mercury levels of 

Great Lakes Herring Gulls. Journal of Wildlife Manage- 
ment 41: 458^68. 
Harris, M. P. 1964. Aspects of the breeding biology of 

the gulls: Larus argentatus, L. fuscus and L. marinus. 

Ibis 106: 432-456. 
Haycock, K. A. and W. Threlfall. 1975. The breeding 

biology of the Herring Gull in Newfoundland. Auk 92: 

678-697. 
Hunt, G. L. 1972. Influence of food distribution and 

human disturbance on the reproductive success of Herring 

Gulls. Ecology 53: 1051-1061. 
Hunt, G. L. and M. W. Hunt. 1976. Gull chick survival: 

The significance of growth rates, timing of breeding and 

territory size. Ecology 57: 52-75. 
Kadlec, J. A. and W. H. Drury. 1968. Structure of the 

New England Herring Gull population. Ecology 49: 

644-676. 
Keith, J. A. 1966. Reproduction in a population of Herring 

Gulls {Larus argentatus) contaminated by DDT. Journal 

of Applied Ecology (Suppl.) 3: 57-70. 
Morris, R. D. and G. T. Haymes. 1977. The breeding 

biology of two Lake Erie Herring Gull colonies. 

Canadian Journal of Zoology 55: 796-805. 
Nisbet, L C. T. 1975. Selective effects of predation in a tern 

colony. Condor 77: 221-226. 
Nisbet, L C. T. and W. H. Drury. 1972. Post-fledging 

survival in Herring Gulls in relation to brood size and 

date of hatching. Bird-Banding 43: 161-172. 
Parsons, J. 1970. Relationship between egg size and post 

hatching chick mortality in the Herring Gull (Larus 

argentatus). Nature (London) 228: 1221-1222. 
Parsons, J. 1971. The breeding biology of the Herring 

Gull {Larus argentatus). Ph.D. thesis, University of 

Durham, Durham, England. 
Paynter, R. A. 1949. Clutch size and the egg and chick 

mortality of Kent Island Herring Gulls. Ecology 30: 

146-166. 
Reynolds, L. M. 1969. Polychlorinated biphenyls (PCB's) 

and their interference with pesticide residue analysis. 

Bulletin of Environmental Contamination and Toxi- 
cology 4: 128-143. 
Ryder, J. P. 1974. Organochlorine and mercury residues in 

gulls' eggs from western Ontario. Canadian Field- 
Naturalist 88: 349-352. 
Teeple, S. M. 1977. Reproductive success of Herring Gulls 

nesting on Brothers Island, Lake Ontario, in 1973. 

Canadian Field-Naturalist 91: 148-157. 
Vermeer, K. 1970. Breeding biology of California and 

Ring-billed Gulls: a study of ecological adaptation to the 

inland habitat. Canadian Wildlife Service Report Series 

12: 1-50. 



Received 2 August 1977 
Accepted 30 September 1977 



Bird Use of a Beaufort Sea Barrier Island in Summer 

Douglas Schamel 

Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99701 

Schamel, Douglas. 1978. Bird use of a Beaufort Sea barrier island in summer. Canadian Field-Naturalist 92(1): 55-60. 

The number and distribution of birds near a barrier island west of Prudhoe Bay, Alaska, were recorded during the 
phenologically "late" summer of 1972. During eastward (spring) migration, most birds were restricted to a small area of open 
water in the nearby river delta. Although numerous eiders (Somateria sp.) fed and rested in the island area during spring 
migration, few did so in late summer, when Oldsquaws (Clangula hyemalis) and Red Phalaropes (Phalaropus fulicarius) 
congregated near the island. 

Key Words: Alaska, arctic, Beaufort Sea, birds, eider, loon, Oldsquaw. 



Knowledge of bird use of Alaskan Beaufort 
Sea coastal waters is limited to a few offshore 
surveys (Bartels 1973; Frame 1973; Watson and 
Divoky 1974) and nearshore reconnaissance 
studies (W. T. Schmidt, unpublished report; 
Bartels 1973; Divoky et al. 1974; Watson and 
Divoky 1974; G. E. Hall, unpublished report). 
These studies all demonstrate the importance of 
nearshore coastal waters to birds, particularly 
sea ducks and phalaropes, in late summer. 
P. G. Connors (unpublished report) and D. 
Schamel (unpublished report) were the first to 
quantify seasonal changes in bird numbers along 
Alaska's north coast; both reported heavy bird 
use of nearshore waters in late summer. 

Some nearshore areas of the Alaskan Beau- 
fort Sea have already been leased to oil 
companies by the state of Alaska. In addition, a 
joint state and federal lease sale is tentatively 
planned for this area in 1979. With the imminent 
expansion of oil development to numerous 
barrier islands along this coast, the extent to 
which birds rely on nearshore waters needs 
documentation. This paper documents changes 
in bird numbers over time and space near a 
barrier island during a single summer. 

Study Area and Methods 

The study was conducted 20 May - 12 August 
1972 from a temporary camp on Egg Island, 
Alaska (70°26'N, 148°43'W), a barrier islet on 
the Beaufort Sea coast, 8 km northwest of 
Prudhoe Bay and 4 km northeast of the Kup- 
aruk River delta (Figure 1). The island is small 
(7.5 ha) and flat (maximum elevation 1 .7 m) and 
is comprised of sand and gravel. Only four plant 
species were found: Honckenya peploides {sand- 
beach sandwort), Mertensia maritima (oyster- 



leaf), Elymus arenarius mollis (lyme grass), and 
Puccinellia phryganodes (alkali grass). During 
winter and early spring the island is icebound. 
After spring break-up the north shore is exposed 
to the action of waves and ice. Although tide 
fluctuations for this area average 1 5 cm. changes 
in wind direction and velocity can cause greater 
variations in water level. 

In 1972, overflow waters from the Kuparuk 
River reached Gwydyr Bay (Figure 1) on 1 June. 
By 6 June the overflow was beginning to drain 
through holes in the ice, and by 10 June some 
previously flooded areas of bay ice were dry. On 
14 June Kuparuk River water was cutting a large 
lead in the bay ice west of Egg Island. By 16 June 
the lead had extended eastward, to include the 
southwest end of the island, and northward into 
the sea. The entire south shore of the island was 
ice-free on 20 June and 70% of the bay was ice- 
free by 28 June. 

Gwydyr Bay is considerably shallower than 
the adjoining section of the Beaufort Sea. Water 
depths in the bay range from 1 .0 to 2.5 m; depths 
at sea range from 2.0 to 5.0 m in the study area. 
Tidal movement temporarily concentrates 
marine invertebrates by forcing them through 
narrow (5-10 m wide) and shallow (0.3-1.0 m 
deep) areas between the gravel islands. Birds and 
fish (arctic char, Salvelinus alpinus) are drawn to 
these passes to feed upon mysids, amphipods, 
and isopods. 

Censuses were made by two individuals (one 
observer and one recorder) from 12 June 
through 7 August 1972, using a 20X spotting 
scope from an elevated blind on Egg Island. 
During a census count (an observation period) 
all birds within a 1.8-km radius (Figure 1) were 
identified with respect to species, sex, location. 



55 



56 



The Canadian Field-Naturalist 



Vol. 92 




km 



Study 
Area 



^. 



Sea 
Bay 



Figure 1. Map of study area. Egg Island, Alaska. 



and activity. The 10.2-km- study area was 
subdivided into three regions: sea (5.3 km-), 
islands (0.2 km-), and bay (4.7 km-). The dura- 
tion of a census count varied from 20^0 min 
(early June) and 50-70 min (July and August) to 
90-110 min (late June), depending upon bird 
numbers in the area. The variable duration of the 
counts does not invalidate the data, since most 
birds were sedentary during censuses. 

Most observed migratory movements occur- 
red seaward of the study area. Eighty-four hours 
of census data were analyzed. The census 
schedule is summarized in Figure 2. Variable 



censusing effort is partly due to frequent bad 
weather; no censuses were conducted when fog 
obscured any part of the study area. In addition, 
censuses were minimized when eiders were active 
on the island, since their activities formed my 
primary study (Schamel 1974, 1977). 

Results and Discussion 

Several species occurred in large numbers, at 
least seasonally, or were ubiquitous in the near- 
shore area. These include Yellow-billed Loon 
(Gavia adanisii), Arctic Loon (Gavia arctica). 
Red-throated Loon {Gavia stellata). Common 



1978 



SCHAMEL: BARRIER ISLAND BiRD USE, BEAUFORT SEA 

AUGUST 



57 



C/5 

Q 
O 

E 1i 

UJ 



< 14 
> 

LU 
CO 
00 

o 

i^ 10 l-ci 

O 

cc 

LU 

m 



6 - 



2 - 



JUNE 
20 
■ ■ ■ ■ 



30 



- dc 



JULY 
10 20 

■■■■■■ L. 



30 



a CD a a 

O a □ D lOD OD □ oo 



1 I r 
30 



lOD ZJD O 
I. . .' J 



2200 



- 1800 



1400 ^ 



> 

O 
a 

1000 !^ 



- 0600 



an D -I 0200 

□ a 



T I r 
30 



TTT 



20 30 10 20 

JUNE JULY AUGUST 

Figure 2. Daily number (square) and time coverage (line) of observation periods. 



Eider (Somateria mollissima v-nigra). King 
Eider {Somateria spectabilis), Oldsquaw (Clan- 
gula hyemalis). Red Phalarope {Phalaropus 
fulicarius). Glaucous Gull {Larus hyperboreus), 
and Arctic Tern {Sterna paradisaea). 

The summer of 1972 was phenologically "late" 
in the Prudhoe Bay area. The mean hatching 
date of eider nests on Egg Island was 6 days later 
than in 1971. Similar phenological delays were 
recorded in the Prudhoe area in 1 972 for tundra- 
nesting waterbirds (Bergman et al. 1977) and 
insects (MacLean 1975). In "late" summers 
fewer nests are initiated, smaller clutch sizes 
prevail (Barry 1960), and renesting is less likely 
than during "normal" summers. Thus, produc- 
tion of young and the summer activity patterns 
and distribution of birds may vary greatly 
between phenologically "normal" and "late" 
summers. The reader is cautioned that data 
presented here were not collected during a 
"normal" summer. 



Loons 

Numbers of loons (all species) peaked on 
16 June (3.9 birds/ km^) and thereafter de- 
creased steadily. On the last census, 7 August, 
only one loon was seen in the study area. The 
occurrence of loons in large numbers near Egg 
Island during mid-June was probably due to 
limited open water and, therefore, limited 
feeding areas, and to the presence of spring 
migrants. The dwindling number of loons in the 
island area thereafter was probably due to the 
availability of food resources inland and in other 
areas along the coast (inland ponds thawed 
about 20 June 1972 (Howard 1974)). 

Throughout the summer, more loons were 
found at sea (x = 1 .6 birds/ km^) than in the bay 
(x = 0.6 birds/ km-). The heterogeneity chi- 
square test (Zar 1974) isolated three portions of 
the summer that could justifiably be pooled for 
normal chi-square analysis: 12 June - 10 July, 
11-27 July, and 28 July - 7 August. Signifi- 



58 



The Canadian Field-Naturalist 



Vol. 92 



cantly more loons used the sea from 12 June to 
10 July than the bay (x^ = 92.2, P< 0.001). 
During the period 11-27 July, both areas 
received equal use (x- = 0.07, 0.90 < P<0.95). 
Slightly more loons were observed in the bay (8) 
than the sea (5) from 28 July to 7 August, 
although this relationship could not be tested 
statistically. 

Loon numbers showed a daily pattern. These 
birds were most numerous near the island from 
0800 to 1600 hours and least numerous from 
2000 to 0200 hours (Alaska Daylight Time). 
During late night and early morning hours, I 
observed that loons are most common on inland 
lakes and ponds where they were nesting. 

Eiders 

Small numbers of eiders were seen in the study 
area beginning on 2 June, 1 day after the waters 
of the Kuparuk River (Figure 1) overflowed 
onto the Gwydyr Bay ice. Small numbers of 
eiders were present in the study area before 
censusing started on 12 June. 

Eastward (spring) eider migration apparently 
occurs largely offshore (Barry 1968; S. R. 
Johnson, personal communication). At Oliktok 
Point, 25 km west of Egg Island, Flock (1973) 
recorded heavy eastward migration at sea in late 
May 1972. I saw the fringe of heavy movements 
on 4 June, more than 2 km north of Egg Island. 
At this time few eiders (< 1 bird/ km^) were seen 
in the study area, which was still ice-covered. As 
shore leads opened, eiders became more numer- 
ous near barrier islands. Eider numbers in the 
study area rose quickly from 12 June (0.3 
Common Eiders/ km^; 0.8 King Eiders/ km^) to a 
peak on 18-19 June (25.7 Common Eiders/km-; 
56.7 King Eiders/ km-), then decreased rapidly. 
By 27 June only 2.9 Common Eiders/ km- and 
14.9 King Eiders/ km- were seen. Numbers 
continued to decrease throughout the field 
season. On 7 August, the date of the last census, 
no birds of either species were seen. Almost all 
migrants were found on open water at sea; few 
used the bay. 

Eiders were present on barrier islands from 
18 June to 4 August. Peak numbers occurred 
from late June through mid-July (about 100 
Common Eiders/ km-; about 50 King Eiders/ 
km-). Birds on the islands represented nest- 
initiating pairs, incubating females, and non- 
breeding females. I located 39 Common Eider 



nests and 3 King Eider nests on Egg Island in 
1972, of which 33% produced young (Schamel 
1974, 1977). 

Westward (post-breeding) migration through 
the study area began in early July (Schamel 
1974). As in the Canadian Beaufort Sea (G. F. 
Searing et al., unpublished report), concentra- 
tions of eiders did not occur in nearshore waters 
during westward migration (about 1-2 eiders/ 
km- in late July), probably for two reasons: 
(1) westward migration extends over 2.5 to 3.0 
months, whereas eastward migration is concen- 
trated within 1 .5 to 2.0 months, and (2) in spring, 
open water is limited and birds congregate where 
leads are available, whereas in summer open 
water occurs along almost the entire shoreline 
and birds are able to disperse. Bartels( 1973) flew 
aerial surveys and made shipboard observations 
from Barrow to the Sagavanirktok River delta 
(just east of Egg Island) from mid-August 
through mid-September 1971. He found the 
greatest concentration of eiders 13-16 km from 
shore. Within 8 km of shore, the mean eider 
density was 1.6 birds/ km-. The highest concen- 
tration of eiders he reported was 4.1 birds/ km^. 

Oldsquaws 

Oldsquaws showed a general numerical in- 
crease from mid-June through early August. 
Small numbers of Oldsquaws were seen during 
June (about 1-13 birds/ km-). Numbers in- 
creased rapidly from early through mid-July 
(about 37-70 birds/ km-), then increased only 
slightly. The rapid increase in early July prob- 
ably represented the arrival of males from inland 
nesting areas and the arrival of late non-breeding 
migrants. The sex ratio in a flock of 130 
Oldsquaws nesting on Egg Island on 5 July was 
2.9 males: 1.0 females. With the end of inland 
nesting in mid-July, additional males moved to 
the coast (Bergman 1974). 

Oldsquaws began molting in mid- to late July. 
Moltitig birds seemed to prefer the bay (lee) side 
of the island. More than 90% of the Oldsquaws 
were found at sea until early July; thereafter, 
coincident with molting, an increasing propor- 
tion used the bay. Approximately 80% of the 
Oldsquaws were found in the bay by August. 

The late summer aggregation of Oldsquaws in 
nearshore waters seems to be a common phe- 
nomenon on the Beaufort Sea coast. Bartels 
(1973) found Oldsquaws concentrated (173 



1978 



SCHAMEL: BARRIER ISLAND BiRD USE, BEAUFORT SEA 



59 



birds/ km-) 3-8 km from shore in late summer. 
Early August densities for the Gwydyr Bay in 
1972 were 70-189 Oldsquaws/km-. Elsewhere, 
W. T. Schmidt (unpublished report) estimated 
6000 Oldsquaws in a bay near Nuvagapak Point, 
Alaska, near the Canadian border in late August 
1970, and G. E. Hall (unpublished report) noted 
a single flock of 5000 birds in Simpson Lagoon, 
about 25 km west of the study area, in mid- 
August 1971. Vermeer and Anweiler (1975) 
counted 2450 Oldsquaws in late August 1973 
near Herschel Island, Yukon Territory. 

Red Phalaropes 

Red Phalaropes are shorebirds that spend the 
non-breeding season at sea and June migrants 
were observed flying from the sea towards the 
coast. Peak phalarope numbers in mid-June 
(about 1.5 birds/ km2) in the study area coin- 
cided with the start of nesting inland in 1972 
(Bergman et al. 1977). The small number of 
phalaropes seen in the study area in late June 
(< 0. 1 bird/ km-) corresponded to the departure 
of females from the breeding grounds ( Bergman 
et al. 1977). In early August young phalaropes 
flew to the coast, where they congregated in 
nearshore waters (about 8 birds/ km-; they 
apparently are also found at least 80 km out to 
sea at this time (Frame 1973). Farther west, at 
Barrow, Red Phalaropes follow a similar pattern 
of seasonal habitat use (P. G. Connors, un- 
published report). 

Glaucous Gulls 

These birds were present in the study area 
throughout the entire field season at a maximum 
of 3^ gulls/ km2. Only three pairs of Glaucous 
Gulls nested on Egg Island in 1972, of which two 
pairs successfully hatched eggs. All young dis- 
appeared from the island within 10 days of 
hatching. With the exception of one day in mid- 
July, gull numbers steadily declined from late 
June through August. These birds apparently 
moved to offshore areas (see Watson and 
Divoky 1974). Frame (1973) saw few Glaucous 
Gulls in offshore waters during early August 
1969, suggesting that the early departure from 
nearshore waters in 1972 may have been caused 
by breeding failures. Watson and Divoky ( 1 974) 
reported poor reproductive success in Glaucous 
Gulls on barrier islands along the Alaskan 
Beaufort coast in 1972. 



Arctic Terns 

Arctic Terns were first noted on 2 June. By 
9 June some were displaying and forming nest 
depressions on the island. Peak tern numbers in 
mid-June (about 1.5 birds/ km-) probably cor- 
responded to the limited open water and, to a 
lesser extent, the end of spring migration. At this 
time, numerous terns were establishing terri- 
tories on the island and feeding in nearby waters, 
mostly at sea. After 1 July, all but one 
pair had abandoned nesting attempts and 
departed from the study area. The remaining 
pair produced two young, both of which died 
less than a week after hatching. In 1972, only an 
occasional tern was seen after mid-July. Frame 
(1973) saw no terns in offshore waters in early 
August. Watson and Divoky (1974) recorded 
some terns in offshore waters through Sept- 
ember. They also found few young terns on 
Beaufort Sea barrier islands in 1972. 

Terns showed strong daily activity patterns. 
They were most numerous in the study area from 
2200 to 0600 hours. During mid-day (1000 to 
1 200 hours) a mean number of less than one bird 
was seen. Terns are visual hunters and probably 
require good lighting for success. They spent the 
brightest part of the day foraging away from the 
island, returning at night. 

Other Birds 

Numerous Black Brant {Branta bernicla ni- 
gricans) migrated past Egg Island, but most 
movements occurred outside the study area. Few 
Surf Scoters {Melanitta perspicillata) were seen 
in the island area, although a group of 200-300 
was seen in Harrison Bay in August 1971 (G. E. 
Hall, unpublished report), and Vermeer and 
Anweiler (1975) recorded up to 3200 in Herschel 
Island bay on 5 August 1973. 

Other birds were seen only in small numbers in 
the Egg Island area in 1972. These included 
Canada Goose {Branta canadensis). Pintail 
{Anas acuta). Greater Scaup {Aythya marila). 
Spectacled Eider {Somateria fischeri). White- 
winged Scoter {Melanitta deglandi). Red- 
breasted Merganser {Mergus serrator), Ameri- 
can Golden Plover {Pluvialis dominica). Ruddy 
Turnstone {Arenaria interpres). Dunlin {Cali- 
dris alpina), Semipalmated Sandpiper (Ca//V/m 
pusilla), Pomarine Jaeger {Stercorarius pomari- 
nus). Parasitic Jaeger {Stercorarius parasiticus). 



60 



The Canadian Field-Naturalist 



Vol. 92 



Long-tailed Jaeger {Stercorarius longicaudus). 
Black-legged Kittiwake {Rissa thdactyla), 
Sabine's Gn\\{Xemasabmi),J\\\c\i-b\\\td Murre 
{Uria lomvia). Black Guillemot [Cepphus 
grylle). Snowy Owl {Nyctea scandiacd), redpoll 
{Acanthis sp.), and Snow Bunting {Plectro- 
phenax nivalis). 

Acknowledgments 

My field work was supported by Federal Aid 
in Wildlife Restoration funds, administered 
through the Cooperative Wildlife Research 
Unit, University of Alaska. Data analysis was 
funded by the Outer Continental Shelf Environ- 
mental Assessment Program, under contract to 
the Institute of Marine Science, University of 
Alaska. Work there was conducted under the 
auspices of G. J. Mueller. I particularly thank 
D. A. Prescott, my field assistant, and T. T. 
Wetmore, my computer programmer. J. C. 
Bartonek helped to formulate this study and 
reviewed the manuscript. D. R. Klein, S. F. 
MacLean, Jr., E. Tull, A. J. Erskine, B. Kessel, 
and G. C. West kindly provided critical review 
of the manuscript. 

Literature Cited 

Barry, T. W. 1960. Breeding history of the Atlantic Brant 

(Branta bernicla hrota). M.Sc. thesis, Cornell University. 

Ithaca. 81 pp. 
Barry, T. W. 1968. Observations on natural mortality and 

native use of eider ducks along the Beaufort Sea coast. 

Canadian Field-Naturalist 82(2): 140-144. 
Bartels, R. F. 1973. Bird survey techniques on Alaska's 

north coast. M.Sc. thesis, Iowa State University, Ames. 

45 pp. 
Bergman, R. D. 1974. Wetlands and waterbirds at Point 



Storkersen, Alaska. Ph.D. thesis, Iowa State University, 
Ames. 58 pp. 

Bergman, R. D., R. L. Howard, K. F. Abraham, and 
M. W. Weller. 1977. Water birds and their wetland re- 
sources in relation to oil development at Storkersen Point, 
Alaska. United States Department of the Interior, Fish 
and Wildlife Service Resource Publication 129. 

Divoky, G. J., G. E. Watson, and J. C. Bartonek. 1974. 
Breeding of the Black Guillemot in northern Alaska. 
Condor 76(3): 339-343. 

Flock, W. L. 1973. Radar observations of bird movements 
along the Arctic coast of Alaska. Wilson Bulletin 85(3): 
259-275. 

Frame, G. W. 1973. Occurrence of birds in the Beaufort 
Sea, summer 1969. Auk 90(3): 552-563. 

Howard, R. L. 1974. Aquatic invertebrate-waterbird re- 
lationships on Alaska's arctic coastal plain. M.Sc. thesis, 
Iowa State University, Ames. 49 pp. 

MacLean, S. F., Jr. 1975. Ecology of tundra invertebrates 
at Prudhoe Bay, Alaska, hi Ecological investigations of 
the tundra biome in the Prudhoe Bay Region, Alaska. 
Edited by }. Brown. Biological Papers of the University of 
Alaska, Special Report Number 2. pp. 115-123. 

Schamel, D. L. 1974. The breeding biology of the Pacific 
Eider {Somaleria mollissima v-nigra Bonaparte) on a 
barrier island in the Beaufort Sea, Alaska. M.Sc. thesis. 
University of Alaska, Fairbanks. 95 pp. 

Schamel, D. 1977. Breeding of the Common Eider (So/»a- 
teria mollissima) on the Beaufort Sea coast of Alaska. 
Condor 94(4): 478^85. 

Vermeer, K. and G. G. Anweiler. 1975. Oil threat to 
aquatic birds along the Yukon coast. Wilson Bulletin 
87(4): 467-480. 

Watson, G. E. and G. J. Divoky. 1974. Marine birds of the 
western Beaufort Sea. In The coast and shelf of the Beau- 
fort Sea. Edited by J. C. Reed and J. E. Sater. Arctic 
Institute of North America, pp. 681-695. 

Zar, J. H. 1974. Biostatistical analysis. Prentice-Hall Inc., 
Englewood Cliffs, New Jersey. 

Received 22 April 1977 
Accepted 23 November 1977 



Recoveries of Saskatchewan-banded Great 
Horned Owls 



C. Stuart Houston 



863 University Drive, Saskatoon, Saskatchewan S7N 0J8 

Houston, C. Stuart. 1978. Recoveries of Saskatcliewan-banded Great Horned Owls. Canadian Field-Naturalist 
92(1): 61-66. 

From 2229 flightless young Great Horned Owls, Bubo virginianus. that I banded in Saskatchewan, there have been 209 
recoveries to date. Owls most commonly were shot, caught in traps, found dead, killed on highways, and electrocuted. Over 
half the recoveries were in the first year of life, and in the first six months most of these were within 10 km of the nest site. The 
oldest owl was trapped 13 years, 6'/: months after it was banded. During years of decreased reproductive success, evidently 
related to decreased food supply, the owls move much farther than in "build-up years." Of the 36 recoveries beyond 250 km, 35 
were in a remarkably consistent southeasterly direction. 

Key Words: Great Horned Owl, banding, longevity, movements. 



My owl Studies grew innocently from random 
banding of any bird at hand, including 15 Great 
Horned Owls, Bubo virginianus, during my first 
15 years of banding. One of these 15 owls was 
shot locally, but another was found injured at 
Bluffton, Minnesota, 730 km to the southeast, 
an unusual distance for a supposed year-round 
resident to travel. 

A review of the literature then disclosed that 
the farthest reported movement of this species 
was by an individual banded at Muscow, 
Saskatchewan, by John R. Carter, and shot over 
160 km to the southeast (Lincoln 1939). Further 
evidence for a south or southeasterly movement 
could be inferred from careful subspecific 
determinations of Great Horned Owl specimens 
from Nebraska and the Dakotas (Swenk 1937). 
Swenk's studies indicated that many of the owls 
shot in fall and winter in Nebraska and the 
Dakotas must have originated from Canada. My 
interest was aroused, and an extensive banding 
program commenced. 

Methods 

My efforts were first aided by 15-year-old Bill 
Horseman, who located 5 nests near Saltcoats in 
1958 and 23 nests in 1959. In 1960, 1 had a weekly 
birdwatching program on the Yorkton television 
station, sponsored by the Brooke Bond Com- 
pany to promote the Peterson bird cards in their 
tea and coffee. Peterson's Field Guides were 
offered as prizes to the boys finding the most owl 
nests, and 150 flightless young were banded. 

After I moved from Yorkton to Saskatoon, 
annual requests in Doug Gilroy's nature column 



in the Western Producer resulted in many 
reports of owl nests from interested farmers, 
many of whom have continued to locate nests 
each year. School teachers at Yellow Creek and 
Crystal Springs interested their pupils in the 
project. 

Nestling owls were banded on evenings and 
weekends throughout May and occasionally 
into June, most within a 250-km radius centered 
75 km east of Saskatoon. I was assisted by many 
enthusiastic students who climbed the most 
difficult trees. We travelled up to 1900 km per 
weekend, banding as many as 61 nestling Great 
Horned Owls in 23 nests in 1 day. With visits to 
1015 successful nests, 2204 nestlings and another 
25 fledglings out of the nest were banded. 

Results and Discussion 

The reproductive success of these owls 
through 1975 has been described previously 
(Houston 1971, 1975). 

From the 2229 flightless young banded, there 
have been 209 recoveries, a rate of 9% to date, 
projected to reach nearly 10% when all 
recoveries from these birds have been received. 
This compares with a recovery rate of 23% on all 
available North American bandings of 478 
nestlings through 1941 (Hickey 1952). 

Means of Recovery 

The commonest reported reason for recovery 
was "shot," and the second "caught in trap" 
(Table 1 ). Twenty-four of the latter were in pole- 
traps at a single game farm near Saskatoon, and 
most of the remaining 1 7 were in traps set for fur- 



61 



62 



The Canadian Field-Naturalist 



Vol. 92 



Table I- 



-How 209 banded Great Horned Owls were 
recovered 



Owls recovered 


Number recovered 






Banded 


Banded 






through 


1968 & 






1967 


after 


Total 


Shot 


34 


22 


56 


In trap 


20 


21 


41 


Found dead 


12 


29 


41 


Hit by car 


4 


11 


15 


Dead on highway 


7 


7 


14 


Electrocuted 


3 


10 


13 


Skeleton or band only 


5 


6 


11 


Injured 


3 


3 


6 


Miscellaneous* 


4 


8 


12 


Total 


92 


117 


209 



♦Includes two each caught in building, caught in fence, 
caught by hand, and hit by train, and one each drowned, 
caught by dog, caught in Bal-Chatri banding trap, and 
collected as scientific specimen. 

bearing animals such as muskrats. Twenty-nine 
owls died on highways. 

There was a statistically significant decline 
from 37% to 1 9% {P < 0.0 1 5 by chi-square, 1 df) 
in owls reported shot in the more recent of the 
two periods (Table 1), perhaps reflecting the 
gradual public awareness of the increased 
protection afforded hawks and owls by 1960 



legislation in Saskatchewan, and possibly a 
tendency to report birds shot as being found 
dead. As highways improved, more owls were hit 
by cars, and as farms received electricity, more 
owls were electrocuted, though these increases 
are too small to show a statistically significant 
difference. 

Mortality and Longevity 

As reported by Hickey (1952), band recoveries 
suggest a high mortality in the first year of life. 
Almost half of my recoveries ( 1 02 of 209) were in 
the same calendar year as banding, and another 
26 occurred in the first 4 months of the following 
year, for a total of 61% within the first year of 
life. Subsequent years were calculated as ending 
each 30 April (Table 2). 

Fifteen recoveries were of owls 5 years old or 
more. The oldest in this series was Number 
508-08090, banded in a nest found by Bill 
Horseman near Bredenbury, Saskatchewan 
(50°50'N, 102°20'W), on 17 May 1959 and 
caught in a trap at Roblin, Manitoba (51°20'N, 
101°20'W), on4 December 1972. Hickey (1952) 
and Kennard (1975) referred to a Great Horned 
Owl, banded by Emerson A. Stoner in Cali- 
fornia, recovered 12 years and 8 months after 
banding, and Stewart (1969) reported another 



Table 2 — Time of recovery after banding for 209 Great Horned Owls 



Year 
banded 



Number 
banded 



Time of recovery in years 

0-1 1-2 2-3 3-4 4-5 5-6 6-7 7-8 9-10 13-14 ?t Total 

1 i_________2 

3 i_________4 

4 4 — 1— — 1— — 1— 11 
7 44141— — — — — 21 

3 i__]_____i 6 

8— — — — — — 1— — — 9 

3________ —3 

811 — 1— — — — — 11 

18 1 2 — — 1 1 1 1 — 25 

20 8 3 — — 2 — — — 33 

11 6 1 3 — 2 — 1 — 24 

11 4 I 1 — 2 — 1 20 

5 3 — — — — — 8 
15 

1 

2 
4 
4 



1946 

M958 

1959 

a 960 

1961 

1964 

1965 

1966 

■1967 

M968 

M969 

= 1970 

1971 

1972 

1973 

1974 

1975 

1976 



1957 



Total 



15 

22 

70 

150 

35 

69 

13 

116 

258 

402 

224 

285 

135 

168 

50 

65 

145 

107 

2229 



128 



3 — 



40 



12 



209 



tSkeleton found; year of death not known. 
*Build-up years (see text). 



1978 



HOUSTON: Saskatchewan-banded Owl Recoveries 



63 



Table 3 — Distance of Great Horned Owl recoveries in different months 



Month ot 




Distance (k 


m) 


— 


1st 


12 


months 






Distance 


(km)- 


later years 




recovery 


0-10 


11-40 


4; 


1-120 


121-250 


>250 


0-10 


11-40 


41-120 


121-250 


>250 


May 


1 














— 


— 


5 


2 


3 


— 


— 


June 


9 


— 




— 






— 


— 


1 


1 


2 


1 


— 


July 


8 


1 




1 






— 


— 


— 


1 


2 


— 


— 


August 


14 


— 




— 






— 


— 


3 


1 


2 


1 


— 


September 


13 


4 




— 






— 


— 


2 


1 


1 


1 


1 


October 


12 


6 




1 






— 


1 


3 


4 


3 


3 


— 


November 


2 


3 




1 






— 


7 


1 


1 


— 


1 


3 


December 


3 


2 




3 






— 


5 


2 


— 


3 


— 


2 


Autumn 


2 


— 




1 






— 


1 


— 


— 


2 


— 


— 


Winter 


— 


— 




1 






— 


1 


— 


— 


— 


— 


— 


Unknown 


1 


— 




— 






— 


— 


— 


— 


1 


— 


1 


January 


— 


1 




— 






— 


3 


— 


— 


2 


1 


2 


February 


1 


— 




2 






— 


2 


— 


1 


— 


1 


2 


March 


3 


1 




— 






— 


3 


— 


2 


— 


2 


1 


April 


— 


I 




2 






4 


1 


1 


3 


2 


— 


— 


Total 


69 


19 




12 






4 


24 


18 


17 


23 


11 


12 



owl, banded in Iowa on 23 April 1939 and 
recovered near the banding site on 6 October 
1952, 13 years and S'/: months later. The 
Bredenbury owl at 13 years, 6'/2 months appears 
to represent the longest survival of a non-captive 
owl of this species published to date. 

From my data on 207 owls, before receipt of 7- 
and 9-year-old recoveries banded in 1969 and 
1967, Robert S. Adamcik calculated "dynamic" 
mortality rates as follows: 57.3% in the first year, 
44.4% in the second year, and an average of 
28.4% annually thereafter. Adamcik's separate 
calculations for those owls shot or trapped and 
for those dying by other means, showed no 
appreciable difference when applied to my 
results. 

Timing of Movements 

My recoveries indicate that mortality is 
highest in the first six months and that fledgling 
owls are slow to leave the vicinity of their nest 
site. Of 34 recoveries before the end of August, 
only two were 1 1 km or more from the nest site; 
the most distant was an owl that moved less than 
50 km southeasterly along the very highway that 
its nest was beside. Of the 37 recoveries in 
September and October, 35 were within 40 km 
of the nest; the only owl to be recovered beyond 
251 km before the end of October was also the 
only one of the 36 distant fliers to travel in a 
northeast direction. A major southeasterly 
incursion, reaching as far as Iowa and Nebraska, 



then occurred during November and December 
(Tables 3, 5). 

After a single Minnesota recovery at the end 
of the first April, there were then no recoveries of 
owls beyond 251 km in any subsequent years 
between April and August, although recoveries 
beyond this distance recurred in subsequent fall 
and winter months (Table 3). Such data suggest 
that most long-distance dispersals are probably 
seasonal movements, akin to those made by 
other birds such as waxwings and goshawks, and 
that most of these owls return to within 120 km 
of their origin before breeding. 

Direction of Movements 

Special attention was paid to those owls that 
moved more than 251 km, the radius of the main 
banding area. From the beginning, it was 
apparent that they followed an unusually 
consistent southeasterly course, followed to this 
date by 35 of the 36 owls that travelled this 
distance (Figure 1, Table 4). This is statistically 
significant; by direct calculation the possibility 
of this occurring by chance is 3.4 X 10~" . Full 
details of these recoveries are provided in Table 
5. 

Although the greatest human population 
densities are to the southeast of the banding 
area, this can hardly explain the remarkably 
consistent direction of movement shown on the 
map. Some equally well populated areas within a 
I500-km radius are without representation, and 



64 



The Canadian Field-Naturalist 



Vol. 92 




Figure 1 . Movements of greater than 250 km, by 36 Great Horned Owls. Squares— place ofdirect reco\ery in same calendar 
year as banding (10). Triangles— place of recovery in first four months of succeeding year (14). Circles— place ot 
recovery of owls more than I year old (12). Note the consistent direction of travel. 



some of the southeasterly recoveries have been 
from sparsely settled districts. More probably 
the owls are following the aspen-grove and 
mixed-forest areas which slope to the southeast, 
perhaps aided somewhat by prevaiHng north- 



westerly winds. It is also the commonest 
direction to be followed by true migrant species 
leaving our province. 

Shorter movements were more random in 
direction, though here as well there is a slight 



1978 



HOUSTON: Saskatchewan-banded Owl Recoveries 



65 



Table 4- 



Direction (by quadrant) and distance travelled 
bv 209 Great Horned Owls 



Distance 




Direction 






(km) 


NE 


SE 


SW 


NW 


Total 


0-10 


_ 


_ 


_ 


_ 


87 


11^40 


10 


14 


5 


7 


36 


41-120 


12 


10 


7 


6 


35 


121-250 


3 


5 


3 


4 


15 


Over 251 


1 


35 








36 


Total 


26 


64 


15 


17 


209 



Statistically insignificant trend to move in a 
southeasterly or northeasterly direction (Table 
4). 

Relation of Movements to Reproductive Success 
During the "build-up years," 1958-59-60 and 
1967-68-69-70, shown with asterisks in Table 6, 
when reproductive success was above average 
and the population was increasing (Houston 
1975), there was a striking decrease in distance 
travelled as compared to intervening years. 



TABLE 5 — Long-distance recoveries (>251 km) of Great Horned Owls banded in Saskatchewan 



Date and pi 


ace of banding 


Date 


and place of recovery 


Means of recovery 


Distance (km) 
















direction 




June 5/60 


Saltcoats 


Nov. 


17/61 


N of Glenboro, Man. 


Shot 


265 SE 




May 18/70 


Kelliher 


Nov. 


17/71 


Glenburn, N.D. 


Shot 


340 SE 




May 20/72 


S of Kelliher 


Mar. 


30/73 


Wakopa, Man. 


Found dead 


340 SE 




May 20/61 


Bethune 


Fall 


1961 


Willow City, N.D. 


Shot 


400 SE 




May 25/72 


N of Rosetown 


Oct. 


1972 


The Pas, Man. 


Car 


485 ENE 




May 13/72 


Birch Hills 


Nov. 


20/72 


Gladstone, Man. 


In trap 


510 SE 




May 15/60 


MacNutt 


Mar. 


28/65 


Barnesville, Minn. 


Shot 


610 SE 




May 19/75 


E of Stalwart 


Mar. 


19/76 


Bordulac, N.D. 


Found dead 


620 SE 




May 14/66 


Plunkett 


Winter 1967 


Carrington, N.D. 


In building 


660 SE 




May 20/72 


S of Kelliher 


Dec. 


8/72 


Aberdeen, S.D. 


Found dead 


725 SSE 




May 24/56 


W of Yorkton 


Dec. 


17/57 


Bluffton, Minn. 


Injured 


730 SE 




May 21/73 


Strasbourg 


Sept. 


18/74 


Seneca, S.D. 


Found dead 


750 SE 




May 10/69 


Dana 


Jan. 


13/73 


Grand Forks, N.D. 


Shot 


750 SE 




May 22/66 


Oxbow 


Nov. 


26/66 


Little Rock, Iowa 


Shot 


780 SE 




May 20/72 


Theodore 


Apr. 


30/73 


Lowry, Minn. 


Found dead 


795 SE 




May 20/72 


E of Wynyard 


Dec. 


8/72 


Orient, S.D. 


Found dead 


820 SSE 




May 26/75 


W of Meacham 


Nov. 


17/75 


Fargo, N.D. 


Found dead 


830 SE 




May 16/71 


S of Young 


Nov. 


26/71 


Hoven, S.D. 


Found dead 


830 SE 




June 4/61 


Klogei Lake 


Oct. 


10/72 


Rush Lake, Minn. 


Band found 


835 SE 




May 17/64 


Otthon 


Dec. 


29/64 


Ethan, S.D. 


Injured 


870 SSE 




May 24/61 


Aberdeen 


Nov. 


13/61 


Sheldon, N.D. 


Shot 


885 SE 




May 20/72 


E of Wynyard 


Nov. 


12/72 


Pillager, Minn. 


In trap 


895 SE 




June 6/65 


Bradwell 


Dec. 


5/65 


Langford, S.D. 


Found dead 


915 SE 




May 11/69 


W of Kinistino 


Dec. 


23/72 


Detroit Lakes, Minn. 


Car 


925 SE 




May 21/72 


E of Earl Grey 


Feb. 


12/73 


Ivanhoe, Minn. 


Highway 


940 SE 




May 23/71 


E of Wynyard 


Feb. 


4/73 


Douglas Co., S.D. 


Found dead 


965 SE 




June 19/66 


Willowbrook 


Nov. 


26/66 


Worthington, Minn. 


Band found 


980 SE 




May 21/67 


Willowbrook 


Jan. 


15/68 


Meckling, S.D. 


Shot 


990 SSE 




May 16/71 


S of Zelma 


Mar. 


11/72 


St. Leo, Minn. 


Highway 


1015 SE 




May 9/70 


E of Young 


Feb. 


1972 


Dell Rapids, S.D. 


Found dead 


1045 SE 




May 3/70 


Floral 


Jan. 


1974 


Meadowlands, Minn. 


In trap 


1080 SE 




May 14/66 


Yellow Creek 


Feb. 


4/67 


Blaine, Minn. 


In trap 


1175 SE 




May 20/67 


Jansen 


Jan. 


14/68 


Glenville, Minn. 


Shot 


1210 SE 




May 30/76 


S of Kelliher 


Dec. 


12/76 


Geneva, Nebr. 


Injured 


1225 SSE 




May 19/69 


Renown 


Nov. 


22/70 


Irvington, Nebr. 


Shot 


1280 SE 




May 19/69 


S of Young 


Jan. 


5/70 


Burchard, Nebr. 


In trap 


1415 SE 





NOTE: Band numbers and latiiong block coordinates of places of banding and recovery are availale from the author on 
request. 



66 



The Canadian Field-Naturalist 



Vol. 92 



Table 6— Distance of recoveries of Great Horned Owls in build-up years as compared to all other years 









Distance 


(km) 










0-10 


10-40 




41-120 


121-250 


>251 


Total 


Build-up years' 
Other years- 
Totals 


57 
30 

87 


22 
14 

36 




17 
18 

35 


3 
12 

15 


4 
32 

36 


103 
106 

209 



'Build-up years were 1958, 1959, 1960, 1967, 1968, 1969, and 1970. 

-Includes 39 owls banded in build-up years and recovered in other years; only two owls banded in other years were 
recovered in build-up years. 



During the "build-up years," coincident with 
increasing numbers of the Snowshoe Hare, 
Lepus amehcanus (Rusch et al. 1972; Mclnvaille 
and Keith 1 974), 77% of the owls were recovered 
within 40 km of the banding site, and only 7% 
travelled more than 120 km. During other years, 
only 41% were recovered within 40 km, whereas 
an equal 41% travelled 121 km or more (Table 
6). This difference is highly significant (/'<0.001, 
by chi-square test, 2 df). 

The correlation of high reproductive success 
with peaks in the Snowshoe Hare population has 
been noted (Houston 1971, 1975), but is being 
correlated more precisely in a companion paper 
by Adamcik et al. (1978). 

Acknowledgments 

I thank Anthony J. Erskine and Robert W. 
Nero for constructive criticism, Robert S. 
Adamcik for construction of a life table from my 
data, and David V. Houston for the statistical 
analysis. I am indebted particularly to those who 
found the nests of the owls that travelled 
farthest: Peter Boychuk, Gerald Churko, Larry 
Dale, Bob Gillard (2), J. B. GoUop, Rudy 
Hassman, Russell Hendryk, Ron Hilderman, 
Bill Horseman, Mary Houston, Lyall Hunter, 
Bryan Isinger, Ian Lochtie (4), J. W. S. 
McArton, Harold Moldenhauer, Larry Mor- 
gotch, Leif Nordal, Sharon Norlin, Hazel Paton, 
Matt Petrowicz, Norm Quinton, Wayne Re- 
naud, Nancy Robinson (3), Cliff Shaw, Jim 
Slimmon, Lawson Sugden, Anton Waycheshen, 



and Doug Whitfield (2). I found only one of 
these 36 nests myself. 

Literature Cited 

Adamcik, R. S., A. W. Todd, and L. B. Keith. 1978. 
Demographic and dietary responses of Great Horned 
Owls during a Snowshoe Hare cycle. Canadian Field- 
Naturalist. 92(2). In press. 

Hickey,J.J. 1952. Survival studies of banded birds. United 
States Fish and Wildlife Service Special Scientific Report 
Number 15. 

Houston, C. S. 1971. Brood size of the Great Horned Owl 
in Saskatchewan. Bird Banding 42: 103-105. 

Houston, C. S. 1975. Reproductive performance of Great 
Horned Owls in Saskatchewan. Bird Banding 46: 
302-304. 

Kennard, J. H. 1975. Longevity records of North Ameri- 
can birds. Bird Banding 46: 55-73. 

Lincoln, F. C. 1939. Interesting recoveries of banded birds. 
In The book of birds. Volume 2. Edited by G. Gros- 
venor and A. Wetmore. National Geographic Society, 
Washington, pp. 351-372. 

Mclnvaille, W. B., Jr. and L. B. Keith. 1974. Predator- 
prey relations and breeding biology of the Great Horned 
Owl and Red-tailed Hawk in central Alberta. Canadian 
Field-Naturalist 88: 1-20. 

Rusch, D. H., E. C. Meslow, P. D. Doerr, and L. B. Keith. 
1972. Response of Great Horned Owl populations to 
changing prey densities. Journal of Wildlife Manage- 
ment 36: 282-296. 

Stewart, P. A. 1969. Movements, population fluctuations, 
and mortality among Great Horned Owls. Wilson Bulletin 
81: 155-162. 

Swenk, M. H. 1937. A study of the distribution and 
migration of the Great Horned Owls in the Missouri 
Valley region. Nebraska Bird Review 5: 79-105. 

Received 20 May 1977 
Accepted 23 November 1977 



Notes 



Food of Ringed Seals and Bowhead Whales 
near Point Barrow, Alaska 



Lloyd F. Lowry, Kathryn J. Frost, and John J. Burns 

Alaska Department of Fish and Game, Fairbanks, Alaska 99701 

Lowry, Lloyd F., Kathryn J. Frost, and John J. Burns. 1978. Food of Ringed Seals and Bowhead Whales near 
Point Borrow, Alaska. Canadian Field-Naturalist 92(1): 67-70. 

Key Words: Phoca (Pusa) hispida, Balaena mysticetus, interspecific competition, prey. 



Ringed Seals, Phoca (Pusa) hispida, and Bowhead 
Whales, Balaena mysticetus, are ecologically impor- 
tant components of the Chukchi-Beaufort marine 
ecosystem. Ringed Seals are present in the area 
throughout the year in association with sea ice. Their 
numbers and spatial distribution vary greatly in 
relation to seasonal changes in ice cover. Bowhead 
Whales winter in the Bering Sea and summer in the 
Beaufort Sea and Amundsen Gulf. They pass close to 
Point Barrow during their spring and fall migrations. 
Both species are regularly taken by Eskimo hunters 
from the settlement of Barrow. 

Ringed Seals are presently numerous in this region 
and are probably at or near the carrying capacity of 
their habitat. The Bering-Chukchi-Beaufort Sea 
population of Bowhead Whales was greatly reduced 
during the late I9th century and the population is still 
below the level that existed prior to commercial 
whaling. Ecological relationships between these two 
marine mammals are unclear. This note indicates that 
in the vicinity of Point Barrow, Alaska, these two 
species utilize the same primary prey items and hence 
some competition for food may exist. 

Methods and Materials 

Table 1 lists the pertinent information regarding the 
16 Ringed Seals and 2 Bowhead Whales from which 
stomach samples were collected. All animals were 
taken in the vicinity of Point Barrow (7I°23'N, 
156°30'W). Samples utilized included the entire 
contents of stomachs obtained from the seals and 
small subsamples of stomach contents from the 
Bowhead Whales. 

When possible, each animal was weighed and 
measured, and the date, time, and location of capture 
noted. Age determinations for seals were based on 
examination of claws and/ or teeth. All contents of the 
seal stomachs were gently washed on a 1.0-mm mesh 
screen and preserved in 10% formalin for later 
examination. The two subsamples of stomach 



contents from Bowhead Whales were preserved in 
10% formahn. 

Laboratory analysis of material involved macro- 
scopic sorting followed by microscopic examination 
and identification of prey. Food items were identified 
using appropriate taxonomic keys and from voucher 
specimens maintained at our laboratory and at the 
University of Alaska Marine Museum Sorting Center. 
The volume of each type of food was measured by 
water displacement. Where possible, numbers and 
size ranges of prey items consumed were determined. 

Results 

As no clear time-, sex-, or age-related differences in 
diet were apparent, the data from all 16 Ringed Seals 
were pooled. Over three-quarters of the combined 
total volume of food was euphausiids (Thysanoessa 
inermis and T. raschii), which occurred in 11 of 16 
stomachs examined. Gammarid amphipods {Anonyx 
nugax, Gammaracanthus loricatus, Acanthostepheia 
behringiensis, Gammarus zaddachi, and Atylus sp.) 
were also found in 1 1 stomachs but comprised only 
4.6% of the combined total volume. Hyperiid 
amphipods {Parathemisto libellula and P. abys- 
sorum) occurred in seven stomachs, always in 
association with euphausiids, and accounted for 0.3% 
of the total combined volume. Isopods (Saduria 
entomon) were found in only two stomachs but made 
up 15.9% of the total combined volume. This high 
percentage was largely the result of a seal taken on 13 
June 1976 the stomach of which contained 200 ml 
Saduria. Shrimp {Sclerocrangon boreas, Lebbeus 
polaris, and Pandalus sp.), mysids (Mysis litoralis and 
Neomysis rayii), and squid (species unknown) 
appeared in a few stomachs in small volumes. Fishes 
were represented almost entirely by otoliths. Otoliths 
of 30 Polar Cod (Boreogadus saida), two Capelin 
(Mallotus villosus), and one Saffron Cod {Eleginus 
gracilus) were identified. Fish remains occurred in five 
seal stomachs. 



67 



68 



The Canadian Field-Naturalist 



Vol. 92 



Table 1 — Ringed Seal and Bowhead Whale specimens from which stomach contents were examined 



Date of 
capture 



Sex 



Weight 
(kg) 



Standard 
length 



Age 

(yr) 



Source of 
specimen 



Seals 

Feb.-Aug. 1975 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
Apr.-July 1975* 
3 Sept. 1975 
II May 1976 
25 May 1976 
25 May 1976 
13 June 1976 
7 Aug. 1976 
7 Aug. 1976 

Whales 

10 Sept. 1976 

20 Sept. 1976 



M 


— 


86.2 cm 


3 


ADF&G' 


M 


55.5 


119.7 cm 


10 


NARL2 


M 


48.2 


115.4 cm 


11 


NARL 


M 


50.9 


121.5 cm 


17 


NARL 


M 


47.3 


117.8 cm 


10 


NARL 


F 


43.2 


112.5 cm 


13 


NARL 


M 


37.7 


1 10.4 cm 


4 


NARL 


M 


35.0 


1 13.7 cm 


6 


NARL 


M 


53.6 


124.0 cm 


18 


NARL 


F 


11.8 


— 


pup 


ADF&G 


M 


49.8 


121.5 cm 


8 


NMFS3 


M 


— 


106.0 cm 


6 


NMFS3 


M 


— 


97.0 cm 


5 


NMFS3 


M 


59.1 


125.0 cm 


14 


ADF&G 


M 


40.9 


119.1 cm 


8 


ADF&G 


F 


38.6 


114.4 cm 


11 


ADF&G 



16.0 m 

14.3 m 



NMFS" 
NMFS'' 



* Exact date of capture unknown but estimated from reproductive state of specimens. 

1 Provided by Alaska Department of Fish and Game personnel. 

2 Provided by Naval Arctic Research Laboratory personnel. 

3 Provided by Robert Everitt, National Marine Fisheries Service. 

■* Provided by J. R. Patee and Robert Everitt, National Marine Fisheries Service. 



Subsamples of stomach contents from Bowhead 
Whales consisted of 17.5 ml from specimen number 
76-B-6F and 33.0 ml from number 76-B-7F. Since 
only subsamples were examined, pooling of data may 
not be justified. Prey items in the two samples, 
however, were similar and little error should result 
from combining them. 

Euphausiids (all identifiable material was Thy- 
sanoessa raschii) made up 90.3% of the total combin- 
ed volume. Gammarid amphipods {Gammarus zad- 
dachi, Acanthostepheia behringiensis, Monoculoides 
zernovi, and Rozinante fragilis) accounted for 6.9%, 
and the hyperiid amphipod Parathemisto libellula 
made up 2.7%. One sample contained a partial 
carapace of an unidentifiable shrimp, another 
contained a small pebble. 

Discussion 

The primary items found in the stomachs of Ringed 
Seals taken from different geographical regions 
indicate marked variation in food consumed. In an 
examination of 47 Ringed Seal stomachs taken near 
Baffin Island during August and September, Dunbar 
(1941) found that the amphipod Parathemisto 
(= Themisto) libellula was the predominant food. 
Mysids {Mysis oculata) were commonly eaten and 
other amphipods, euphausiids, and fishes were 



occasionally consumed. The same general results were 
reported by McLaren (1958). In the northwestern 
Bering Sea and the Sea of Okhotsk, euphausiids 
( Thysanoessa raschii) appear to be the chief food item. 
Shrimps, amphipods and various schooling fishes are 
sometimes important in the diet (Fedoseev 1965; 
Fedoseev and Bukhtiyarov 1972; Nikolaev and 
Skalkin 1975). Kenyon (1962) found shrimp {Pan- 
dalus sp.) to be the primary food, with fishes, mysids, 
and gammarid amphipods eaten in small quantities in 
Bering Strait during May and June. Johnson et al. 
(1966) in an extensive investigation of the foods of 
Ringed Seals near Point Hope and Kivalina, Alaska, 
found fishes (Boreogadus saida, Eleginus gracilus, 
and cottids) to be the main food during November 
through February. Beginning in March and con- 
tinuing through June, crustaceans (shrimps, am- 
phipods, crabs, and mysids) made up the bulk of the 
Ringed Seal's diet at these locations. Results from 
other localities in the eastern Bering and Chukchi Seas 
follow the same general pattern (Lowry, Frost and 
Burns, unpublished data). 

It appears that food consumed by Ringed Seals at 
any given place and time will consist of the most 
abundant and available suitable species which, in the 
western Beaufort Sea during late spring and summer, 
apparently is euphausiids. It is noteworthy that a seal 



1978 



Notes 



69 



collected 150 km east of Point Barrow, 35 km 
offshore on 20 August 1976 (data not included in this 
report) had also eaten almost entirely euphausiids. In 
247 Ringed Seal stomachs containing food, which we 
have examined from Alaskan waters other than the 
Beaufort Sea, euphausiids have occurred in only 15. 
Of those, 1 1 were taken in the northeastern Chukchi 
Sea, at Point Hope, in late May 1976. 

Bowhead Whales are considered to feed in a 
skimming mode utilizing their highly specialized 
baleen plates (Nemoto 1970). They would therefore be 
expected to feed mostly on copepods and to a lesser 
extent on euphausiids and other zooplankters. 
Tomilin (1957) cited indirect evidence indicating that 
the copepod Calanus finmarchicus and the pteropod 
Limacina helicina are major food items. MacGinitie 
(1955) reported that bowheads (presumably near 
Barrow) ate euphausiids, mysids, pteropods, and 
copepods. Mitchell (1975) indicates that in the eastern 
Arctic, bowheads sometimes eat benthic amphipods 
as well as mysids and other similar zooplankters. 

The results of our very Umited sampling of stomach 
contents from Bowhead Whales agree closely with the 
statements of Mitchell (1975). Euphausiids are, by far, 
the most important food item. Hyperiid amphipods, 
which are apparently associated with swarms of 
euphausiids, were much less common. The finding of 
a considerable number of benthic gammarid amphi- 
pods indicates that bowheads sometimes forage very 
near or on the bottom, at least in shallow-water areas. 
Indications of benthic foraging have been observed 
and photographed during aerial surveys of bowheads 
close to shore immediately east of Point Barrow (J. 
Burns, unpublished observations). 

Bowhead Whales migrate apparently in response to 
seasonal changes in ice conditions. Whales captured 
at Point Hope and Point Barrow during the 
northward spring migration in April through June 
have empty or near-empty stomachs (Johnson et al. 
1966; Durham*; Marquettet; G. Seaman, personal 
communication). Whether bowheads feed on the 
wintering grounds is not known. Suitable types of 
foods are available in portions of the Bering Sea, at 
least during the spring and summer (Nemoto 1957). 

Biological processes in the Beaufort Sea are, to a 
large degree, regulated by the quantity and character 
of sea ice. Bowhead Whales are the most ice-adapted 



*F. E. Durham. 1972. Biology of the bowhead whale 
{Balaena mysticetus L.) in the western Arctic. University 
of Southern California, Los Angeles. Unpublished man- 
uscript. 

tW. M. Marquette. 1977. The 1976 catch of bowhead 
whales {Balaena mysticetus) by Alaskan Eskimos, with a 
review of the fishery, 1973-1976, and a biological sum- 
mary of the species. National Marine Fisheries Service, 
NAFC, Seattle, Washington. Processed report. 80 pp. 



of mysticete cetaceans and Ringed Seals are the most 
ice-adapted pinniped occurring in the northern 
hemisphere. In the northern portion of their range 
these two species show broad dietary overlap. Ringed 
Seals are highly euryphagous, and utilize many 
species of fishes and crustaceans. Bowhead Whales 
are considerably more stenophagous and depend 
mostly on swarms of small to medium-sized zoo- 
plankton. 

The Beaufort Sea experiences extreme year-to-year 
variation in the extent of summer sea-ice cover. 
Although sea ice provides a substrate for a special 
group of algae (Meguroetal. 1966), the primary effect 
of ice cover is a lowering of overall productivity by 
drastically decreasing Ught penetration (Mohr and 
Tibbs 1963). A decrease in the total primary 
production of the area would result in lower 
productivity at higher trophic levels. Stirling et al. 
(1977) speculate that reduced production caused by 
the heavy ice conditions of the winter of 1973-1974 
may have been responsible for an observed decrease in 
productivity of Ringed and Bearded Seals. The long- 
term ecological effect of fluctuations in annual 
production would be difficult to predict. It seems 
likely, however, that short-lived stenophagous species 
would be most rapidly and acutely affected. Specific 
data on trophic interaction of major components of 
the arctic ecosystem are urgently needed as poten- 
tially drastic long-term environmental modifications 
such as offshore oil drilling are imminent. 

Bowhead Whales, which are currently reduced in 
numbers and "officially" considered as a rare and 
endangered species, were once abundant in arctic 
waters. Scheffer (1976) indicates that the pre- 
exploitation population level was composed of about 
10 000 animals and estimated the present population 
to be about 2000. No long-term data are available for 
Ringed Seal numbers. An estimate of the early spring 
population of Ringed Seals in the area where 
bowheads summer (Beaufort Sea and Amundsen 
Gulf) is at least 30 000 animals (Burns and Harbo 
1972; Stirling et al. 1977). This number increases 
greatly during the summer, with the seasonal influx of 
seals from the south. Two interesting questions arise. 
As the bowhead population declined, did populations 
of other marine mammals or birds increase because of 
increased abundance of food? Will Bowhead Whales 
be able to regain their former population levels and, if 
so, will it be at the expense of other species? 
Unfortunately, no data exist to answer the first 
question and too little information is presently 
available adequately to answer the second. 

Acknowledgments 

We express our appreciation to H. Reynolds, R. 
Everitt, and J. R. Patee for assistance in acquiring 



70 



The Canadian Field-Naturalist 



Vol. 92 



specimens, and acknowledge project support pro- 
vided by the U.S. Bureau of Land Management Outer 
Continental Shelf Environmental Assessment Pro- 
gram and Federal Aid in Wildlife Restoration Project 
W-17-9. 

Literature Cited 

Burns, J. J. and S. J. Harbo, Jr. 1972. An aerial census of 
ringed seals, northern coast of Alaska. Arctic 25: 279- 
290. 

Dunbar, M. J. 1941. On the food of seals in the Canadian 
eastern arctic. Canadian Journal of Research 19, Section 
D: 150-155. 

Fedoseev, G. A. 1965. Food of the ringed seal {Pusa 
hispida Schr.). Izvestia TINRO 59: 216-223. 

Fedoseev, G. A. and Y. A. Bukhtiyarov. 1972. Food of the 
seals of the Okhotsk Sea. Tezisy Doklady 5th All- 
Union Conference on Marine Mammals, Makhackhala. 
Part 1. pp. 110-112. 

Johnson, M. L., C. H. Fiscus, B. T. Ostenson, and M .L. 
Barbour. 1966. Marine mammals. /« Environment of the 
Cape Thompson Region, Alaska. Edited by N. J. Wili- 
movsky and J. N. Wolfe. U.S. Atomic Energy Com- 
mission, Oak Ridge, Tennessee, pp. 897-924. 

Kenyon, K. W. 1962. Notes on the phocid seals at Little 
Diomede Island, Alaska. Journal of Wildlife Management 
26: 380-387. 

MacGinitie, G. E. 1955. Distribution and ecology of 
marine invertebrates of Point Barrow, Alaska. Smith- 
sonian Miscellaneous Collections 128(9): 1201. 

McLaren, L A. 1958. The biology of the ringed seal, 
Phoca hispida, in the eastern Canadian Arctic. Bulletin 



of the Fisheries Research Board of Canada 118: 1-97. 

Meguro, H., K. Ito, and H. Fukushima. 1966. Ice flora 
(bottom type): A mechanism of primary production in 
polar seas and the growth of diatoms in sea ice. Arctic 
20: 114-133. 

Mitchell, E. 1975. Trophic relationships and competition 
for food in northwest Atlantic whales. In Proceedings 
of the Canadian Society of Zoologists Annual Meeting, 
June 2-5, 1974. Edited by M. D. B. Burt. pp. 123-133. 

Mohr, J. L. and J. Tibbs. 1963. Ecology of ice substrates. 
In Arctic Basin Symposium, October 1962. Chaired by 
M. J. Dunbar. Proceedings of the Arctic Institute of 
North America, pp. 245-249. 

Nemoto, T. 1957. Foods of baleen whales in the northern 
Pacific. Scientific Reports of the Whales Research 
Institute 12: 33-89. 

Nemoto, T. 1970. Feeding pattern of baleen whales in the 
ocean. In Marine food chains. Edited by J. H. Steele. 
University of California Press, Berkeley, pp. 241-252. 

Nikolaev, A. M. and V. A. Skalkin. 1975. On the food of 
true seals of the eastern coast of SakhaHn. Izvestia 
TINRO 95: 120-125. 

Scheffer, V. B. 1976. The status of whales. Pacific Dis- 
covery 29: 2-8. 

Stirling, L, W. R. Archibald, and D. DeMaster. 1977. 
Distribution and abundance of seals in the eastern 
Beaufort Sea. Journal of the Fisheries Research Board 
of Canada 34: 976-988. 

Tomilin, A. G. ,1957. Mammals of the U.S.S.R. and 
adjacent countries. Volume IX, Cetacea. 

Received 5 July 1977 
Accepted 2 October 1977 



Birds and Mammals as Passive Transporters 
for Algae Found in Lichens 

Craig S. Scharf 

Department of Biology, Southern Connecticut State College 

Present Address: Northeastern Forest Service, 151 Sanford Street, Hamden, Connecticut 06514 

Scharf, Craig S. 1978. Birds and mammals as passive transporters for algae found in lichens. Canadian Field-Naturalist 
92(1): 70-71. 



Although algae are found world-wide, little is 
known about how their distribution is achieved. An 
understanding of algal dispersal may in turn be 
important to understanding lichen distribution. 
Known mechanisms of algal dispersal include wind 
dissemination (Proctor 1959) or transport on the 
external parts of birds (Proctor 1959) and insects 
(Maguire 1959). Opinions vary as to the success with 
which algal symbionts (phycobionts) and fungal 
symbionts (mycobionts) unite in lichen formation. 



This study attempted to determine whether birds and 
mammals could serve as transporting agents for 
phycobionts. 

White-throated Sparrows {Zonotrichia albicoUis), 
Black-capped Chickadees {Parus atricapillus), and 
House Sparrows {Passer domesticus) were mist- 
netted from two separate areas. One area was located 
in Branford, Connecticut in a hardwood-hemlock 
forest, and the other area was a wooded residential 
area in Bethany, Connecticut. White-footed Mice 



1978 



Notes 



71 



{Peromyscus leucopiis) and Red Squirrels (Tamias- 
ciurus hudsonicus) were live-trapped from the first 
area. 

The birds and mammals were "washed" (feet, bills, 
and tails) with distilled water from a squeeze-bottle to 
remove any particulate matter. The wash water was 
drained into sterile dilution bottles in the field and 
later (within 24 h) transferred into 100-ml soil-water 
culture bottles. The soil-water bottles had been 
prepared by combining 0.65 to 1 .5 cm soil (sieved by a 
#10 U.S. Standard Sieve) with 0.001 g CaCO, (to 
neutralize soil acidity) and enough distilled water to 
bring the total volume to 75 ml. They were then 
autoclaved three times at 135°C allowing a 24-h 
interval between autoclavings. The soil-water bottles 
were then individually inoculated with the full 
amount of wash water from each specimen. The 
inoculated soil-water bottles were then placed in a 
culture cabinet, under continuous light at 24° C. After 
1 5 days, random samples from the culture bottles were 
examined microscopically. 

Most of the cultures (from both birds and mam- 
mals) contained algal growth. Some of the algae 



included genera found as lichen phycobionts, Proto- 
coccus, Nostoc, Coccomyxa, Anabaena, Chlorococ- 
cum, and Trentepohlia. One mammal culture con- 
tained Trehouxia, which is rarely found outside of 
lichen thalli (Ahmadjian 1967). Other algae cultured, 
which are commonly found in terrestrial, aquatic, and 
arboreal environments, were Ulothrix, Chlorella, and 
Microspora. 

Clearly, both birds and mammals act as passive 
transporters for viable forms of algae. Therefore, they 
may well be dispersal agents for phycobionts. 

Literature Cited 

Ahmadjian, V. 1967. A guide to the algae occurring as 
lichen symbionts: Isolation, culture, cultural physiology, 
and identification. Phycologia 6: 127-160. 

Fink, B. 1960. The lichen flora of the United States. 
University of Michigan Press, Ann Arbor. 

Maguire, B., Jr. 1959. Passive overland transport of small 
aquatic organisms. Ecology 40: 312. 

Proctor, V. W. 1959. Dispersal of freshwater algae by mi- 
gratory water birds. Science (Washington) 130: 623-624. 

Received 18 April 1977 
Accepted 23 November 1977 



Winter Predation by Black-capped Chickadees and 

Downy Woodpeckers on Inhabitants of the Goldenrod Ball Gall 

Lyanne Schlichter 

Department of Zoology, University of Toronto, Toronto, Ontario M5S lAl 

Schlichter, Lyanne. 1978. Winter predation by Black-capped Chickadees and Downy Woodpeckers on inhabitants of 
the Goldenrod Ball Gall. Canadian Field-Naturalist 92(1): 71-74. 

The goldenrod ball gall larva, Eurosta solidaginis, appears to be a commonly exploited winter food source for the 
Downy Woodpecker, Picoides pubescens, and the Black-capped Chickadee, Parus atricapillus. Downies fed most heavily at 
the forest edge, whereas chickadees used both the forest edge and the open field. Misshapen galls were untouched, their 
rejection apparently based on visual cues. By the end of winter most normal appearing galls were superficially scored, even if 
not opened. Although many of these scored galls had their larvae preyed upon, some were rejected without penetration. 
Rejected galls usually contained dead mature fly larvae or mordellid beetle larvae. 

Key Words: Downy Woodpecker, Black-capped Chickadee, goldenrod gall, prey selection. 



During the winter months, many naturalists have 
seen Downy Woodpeckers (Picoides pubescens) and 
Black-capped Chickadees (Parus atricapillus) on 
stems of goldenrod, pecking at large round galls and 
extracting the inhabitants. Ping (1915) reports that 
these galls are produced on Canada goldenrod 
(Solidago canadensis) by the gall fly Eurosta solida- 
ginis (Diptera, Tephritidae). In examining large 
numbers of these galls I identified three types of 
attack: small clean holes and large irregular holes, 
both reaching into the center of the galls, and 
superficial scoring. Other galls were apparently 



untouched. This food source has not been mentioned 
in surveys of bird feeding habits (e.g., Martin et 
al. 1961). Use of the resource and reasons for 
differences in the type of attack are examined in this 
study. 

Gall Structure 

An adult female gall fly deposits an egg on a 
goldenrod stem in the spring. By early summer the 
larva emerges and burrows into the stem, initiating 
gall formation (Ping 1915). Stems are occasionally 
found on which two or three eggs have been laid, each 



72 



The Canadian Field-Naturalist 



Vol. 92 



producing a galL It is unknown wliether the same 
female is responsible for all larvae on a single stem. 
Proliferation of plant tissue yields an eccentric ball- 
shaped gall though misshapen galls are not uncom- 
mon. In mature galls, a tunnel stretches from the core 
to one edge, terminating just beneath the surface. 
Normal galls that have not been preyed upon contain a 
white larva near the tunnel's outer edge. Three types of 
abnormalities are recorded in this study: 

( 1 ) Gall larvae that have died early in the season or are 
unusually small occupy small misshapen galls. 

(2) Occasionally dead mature larvae are found. 
Mould is usually present in the tunnels of such larvae. 

(3) In addition to the gall-forming larva, a small 
elongate larva of the beetle Mordellistena unicolor 
(Coleoptera, Mordellidae) is sometimes found in a 
separate tunnel (Ping 1915). This second tunnel 
usually lies on the periphery of the fly larva's tunnel, at 
the top of the gall. I never found the two insect species 
in physical contact and, in the presence of the beetle 
the gall fly larva appeared well developed and healthy. 
The relationship between these two larvae has not 
been investigated. 

Study Sites 

One study site was located on a low-lying road 
allowance near Kleinburg, Ontario. It was bounded by 
the junction of two roads, a stream, and a secondary- 
succession forest. At the forest edge grew dense 
clumps of goldenrod, an occasional blackberry 
(Rubus sp.) and a few red-osier dogwood (Cornus 
stolonifera). Close to the road junction there was a 
fairly uniform stand of goldenrod with little else 
visible above the snow. 

At the end of the winter a second site was examined 
on the flood plain of the Thames River near London, 
Ontario. This site was bordered by open fields on three 
sides and a secondary-succession forest on the fourth. 
The nearest road was several hundred yards away. 

Methods 

At the Kleinburg site predation was monitored from 
late November until late February. Two quadrats, 
10 X 10 m, were laid out at the forest edge and another 
two in the open field as far as possible from trees. At 
each visit I collected from each quadrat galls that had 
been penetrated since the last visit. Type of attack and 
proximity to the forest were recorded. 

Comparisons of the degree of predation at the forest 
edge and in the open field were made using data from 
both Kleinburg and London. At the London site one 
quadrat, 30 X 30 m, was laid out at the forest edge and 
a second in the open field at least 130 m from the 
nearest tree. At the end of the winter I counted the 
number of successful attacks by each species on all 
quadrats. 

Predator treatments of normal and abnormal prey 



were studied at both sites. A large sample (335) of 
apparently normal galls was collected. Ninety-four 
small misshapen galls were also collected. These galls 
were dissected and examined with a 20X hand lens. 
Type of attack and the presence of fly and beetle larvae 
were noted. 

In all cases deep narrow holes from 1 .2 cm to 1 .5 cm 
deep were assumed to be made by the forceps-like 
Downy Woodpecker bill. Large, irregular holes were 
attributed to Black-capped Chickadees. I found no 
report of any other short-billed bird attacking these 
galls. Since naturalists report that both species 
sometimes tap galls lightly and abandon further 
attack. I assume that both birds are responsible for 
scoring. 

Results 

Temporal Study 

At the forest edge a decline in predation rate by both 
species was seen after the third week of December 
(Figure 1). By this time 80.5% of available galls had 
been successfully attacked at the forest edge. 

In the open field downies and chickadees showed a 
reduced predation rate by the end of January when 
60% of available galls had been preyed upon by the 
two species of birds. 

The lack of predation by the end of January was not 
due to the birds' disappearance from the site. I 
observed several chickadees and one or two downies 
on the site at each visit during January and February. 

Foraging-site Preference 

By the end of the winter downies had preyed upon 
39 galls in all three open-field quadrats and 101 in the 
three forest-edge quadrats. Black-capped Chickadees 
took larvae from 100 galls in the open field and 91 at 
the forest edge. 

Abnormal Prey 

Of the 335 externally normal galls, 149 were found 
to have internal abnormalities. Only 24.8% of these 
abnormal galls were successfully attacked, compared 
with 73.1% of fully normal galls. Forty-nine of the 149 
abnormal galls contained one or more mordellid 
beetle larvae in addition to the fiy larva. Of these, only 
24.5% had their gall fly larvae removed. None of the 
mordellid beetle larvae were taken by the birds. 

Of the 94 small misshapen galls containing dead, 
immature fly larvae, only 13.8% were preyed upon. 
The remaining 81 misshapen galls showed no scoring 
or any other sign of having been touched by birds. 
Table I summarizes our findings. 

Since the beginning of this study, I have noted 
similar predation patterns in other southern Ontario 
sites. Observations have been made in Elgin, Halton, 
Essex, and Bruce Counties and near Midland, King 
City and Toronto. 



1978 



Notes 



73 



60 



50 



40 



o ^ 
- o 



30 



20 



10 




Legend 

Chickadees- forest 
Downies- forest 
Chickadees- field 
Downies - field 



Nov 
4 



Dec 

1 



Jan 
1 



Feb 
1 



Time (weeks) 



Figure I. Comparison of degree of predation over winter in the open-field and forest-edge habitats at the Kleinburg 
site. Cumulative scores for successful predation are expressed as the percent of galls originally present on the 
quadrats. 



Discussion 

In the temporal study at Kleinburg, the decline in 
predation rate at the forest edge after the third week of 
December probably reflects a dwindling resource. By 
this time 80.5% of available gall larvae were eaten. The 
birds may have had difficulty in finding the remaining 
intact galls. This explanation is not as convincing in 
the open field where only 60% of available fly 
larvae had been taken. 

At the London site, open-field and forest-edge 
quadrats were separated by more than 100 m. By the 
end of winter fewer than 50% of the galls present in 
either quadrat had been preyed upon. In this case 
downies took more gall larvae at the forest edge than 
did chickadees. In the open field chickadees took 



Table I — Comparison of successful predation by Black- 
capped Chickadees and Downy Woodpeckers on normal 
and abnormal galls 



Type of gall 


Number of galls 


with fly larvae 




Eaten 


Uneaten 


Normal 


136(73.1%) 


50 


Misshapen 


13(13.8%) 


81 


Externally normal 
but with internal 
abnormalities 


37(24.8%) 


112 


With beetle 

larvae (included also 
in third line) 


12(24.5%) 


37 



many more larvae than did downies. When data from 
all quadrats are taken together downies attacked more 
than 2.5 times as many galls at the forest edge as in the 
open field. Chickadees, however, took almost equal 
numbers from the two habitats. This suggests a 
foraging-site preference that was not apparent at the 
heavily used Kleinburg site. Such site preferences have 
been reported in the literature. Odum (1941) found 
that Black-capped Chickadees often venture far into 
open fields on feeding forays. Downies seem to prefer 
the forest edge (Lawrence 1967). It may be that lack of 
food at the forest edge forced downies to feed in the 
open field at Kleinburg. 

It is intriguing that abnormal larvae were rejected, 
even in late winter when the supply of normal larvae 
had dwindled. How do the birds make a distinction 
between galls containing normal and abnormal 
larvae? For grossly misshapen galls usually containing 
dead decomposing larvae it is quite possible that 
rejection is based on visual cues alone. Signs of 
physical attack were almost always missing. 

Use of such obvious visual cues cannot explain 
rejection of prey in normal-shaped galls. Some 
naturaUsts maintain that these birds tap galls, listening 
for the hollow ring of an already preyed-upon gall. It is 
possible that the scoring produced by this tapping 
provides information on the internal condition of 
occupied normal-shaped galls. Alterations in gall 
tissue accompanying unhealthy larvae have been 
found for another goldenrod gall maker (Beck 1954). 
Alternatively, either the gall fly larvae or the mordellid 
beetle larvae may themselves produce cues that the 



74 



The Canadian Field-Naturalist 



Vol. 92 



birds can detect. It is likely that the mordellid beetle 
larvae are unpalatable since none of them were eaten. 
Rejection of dead or extremely small larvae with 
low nutritive value may be an energy-conserving 
behavior. This does not explain the rejection of the 
third type of abnormal galls. In this type the presence 
of the mordellid beetle larva seemed not to harm the 
gall fly larva, but rather to protect it from avian 
predation. Further investigation of the "mutualistic" 
relationship between these two insect species is 
necessary. 

Acknowledgments 

I thank J. C. Barlow, Royal Ontario Museum and 
the University of Toronto, and J. Machin and J. 
Rising, University of Toronto, for reviewing earlier 
versions of this manuscript. 



Literature Cited 

Beck, E. G. 1954. The nature of the stimulus in the 5'o//(iag^o 
gall induced by the larva of Gnorimoschema galloeso- 
lidaginis. Brookhaven Symposia in Biology 6: 235-251. 

Lawrence, L. de K. 1967. Life histories of four North 
American Woodpeckers. American Ornithological Mono- 
graphs 5. 156 pp. 

Martin, A. C, H. S. Zim, and A. L. Nelson. 
1961. American wildlife and plants: A guide 
to wildlife food habits. Dover Publications Inc., New 
York. 500 pp. 

Odum, E. P. 1941. Annual cycle of the Black-capped 
Chickadee. Auk 58: 314-333. 

Ping, C. 1915. Some inhabitants of the round gall on 
goldenrod. Journal of Entomology and Zoology 
7: 161-179. 

Received 18 November 1976 
Accepted 2 October 1977 



The Status of Lythrum alatum (Lythraceae) in Canada 



William J. Cody 



Biosystematics Research Institute, Canada Agriculture, Ottawa, Ontario KIA 0C6 

Cody, William J. 1978. The status of Lythrum alatum (Lythraceae) in Canada. Canadian Field-Naturalist 92(1): 74-75. 



There are two species of Lythrum in Canada. The 
Purple Loosestrife, Lythrum salicaria, a species 
introduced from Europe, is a familiar weedy plant in 
wet meadows and along streams through large parts 
of southern Canada. Boivin (1966) reported this 
species as occurring in all the Canadian provinces but 
Saskatchewan, and it is now known from that 
province on the basis of a recent collection from near 
Sutherland {V. L. Harms 18460 (DAO, SASK)). In 
Ontario, many acres of marshes and low wet ground 
are resplendent in purple during the height of the 
flowering season of this plant. 

Lythrum alatum, a less showy purple-flowered 
plant, is a native prairie species, which is widespread 
throughout the United States, but in Canada is known 
only from Ontario and British Columbia although 
Fernald (1950) gave the habitat and range as 
"Swamps, meadows, prairies and ditches, Ont. and n. 
N.Y. to B.C., s. to Ga., La. and Tex.; adv. in N.E., N.J. 
etc." It was first reported as occurring in Canada from 
the area adjacent to the Detroit River in Essex 
County, Ontario, and from Point Edward in Lambton 
County, Ontario, by John Macoun (1883-1886). 
Numerous collections have been made from Lambton, 



Kent, and Essex Counties in the area adjacent to the 
St. Clair River, Lake St. Clair, and the Detroit River 
since that time. Lythrum alatum is certainly of native 
origin there. 

Localities in other parts of Ontario are widely 
separated as demonstrated in Figure 1. With the 
exception of the Elgin County record (Stewart and 
James 1969), the occurrence of L. alatum at a distance 
from the St. Clair River-Lake St. Clair-Detroit River 
area has not previously been reported. It is now 
known from additional localities in the following 
counties (years of collection are given in parentheses): 
Carleton (1952 and 1969), Durham (1898 or 1889, 
1948 and 1952), Elgin (1899, 1968), Essex (1892 and 
1974), Haldimand (1915), Kent (1934, 1948, 1960, 
1962), Lambton (inland collections 1906 and 1947), 
Middlesex (1937), and Norfolk (1961). 

The localities north of Lake Erie, though widely 
separated, may represent a native distribution, 
although the dates of collection might indicate that it 
was adventive at some of the localities. The collections 
from Durham and Carleton Counties are con- 
siderably disjunct from the main range, and may be 
introductions, as Fernald (1950) suggested for the 



1978 



Notes 



75 




Figure 1. The Ontario distribution of Lvthrum alatum as known from the following herbaria: CAN, DAO, OAC, QK, 
TRT, and UWO. 



New England States, but the early date of 1898 (or 
1889) would indicate that it was probably of native 
origin. The Carleton County localities are in the midst 
of the Ottawa-Carleton Regional Forest. The Prairie 
White Fringed Orchid (Habenaha leucophaea), a 
species centered about the lower Great Lakes, has 
only recently been reported here and was formerly 
known from near Port Hope in Durham County 
(Reddoch 1977). This occurrence of a native plant 
with disjunct distribution similar to that of L. alatum 
supports the possibility that L. alatum is also native in 
both Carleton and Durham Counties. 

Lafontaine and White (1974) reported L. alatum 
from Shirleys Bay on the Ottawa River near Ottawa, 
presumably on the basis of a sight record, but this was 
later discounted (White 1977) because no voucher 
specimen could be found, and a detailed search in the 
field failed to turn it up. 

The report from British Columbia (Fernald 1950; 
Henry 1915; Macoun 1895) is based on a collection 
from Griffin Lake in the Kamloops District {John 
Macoun s.n., 6 July 1889, CAN). J. M. Macoun 
(1895) commented "It is possible that the seeds of the 
Griffin Lake plants were in some way introduced, 
though this is not probable." Lythrum alatum has not 
been collected in British Columbia since 1889. The 
British Columbia collection is disjunct from sites in 
the western United States. 

The native L. alatum may be readily distinguished 
from L. salicaria by its linear-lanceolate to oblong- 



ovate rather than lanceolate leaves; single smaller 
flowers in the axils of small usually alternate leaves, 
rather than densely cymose in the axils of whorled or 
opposite leaves; the glabrous narrowly oblong rather 
than more or less pubescent somewhat thickened- 
urceolate calyx; and the wing-margined angles of the 
upper branches and calyx. 

Literature Cited 

Boivin, B. 1966. Enumeration des plantes du Canada. 

Ill — Herbidees, 1° Partie: Digitatae: Dimerae, Liberae. 

Naturaliste Canadien 93: 583-646. 
Fernald, M. L. 1950. Gray's manual of botany. 8th edition. 

American Book Co., New York. 1632 pp. 
Henry, J. K. 1915. Flora of southern British Columbia. 

W. J. Gage and Co. Ltd., Toronto. 363 pp. 
Lafontaine, J. D. and D.J. White. 1974. Ottawa District 

plant survey. Trail & Landscape 8: 85-88. 
Macoun, J. 1883-1886. Catalogue of Canadian plants. 

Volume 1. Dawson Brothers, Montreal. 623 pp. 
Macoun, J. M. 1895. Contributions to Canadian botany. 

VL Canadian Record of Science 6: 318-329. 
Reddoch, J. 1977. Prairie white fringed orchid, a new 

orchid for the Ottawa area. Trail & Landscape 11: 16-19. 
Stewart, W. G. and L. E.James. 1969. A guide to the flora 

of Elgin County, Ontario. Catfish Creek Conservation 

Authority, St. Thomas, Ontario. 118 pp. 
White, D.J. 1977. Rare plant survey: revisions. Trail & 

Landscape 11: 22-25. 

Received 4 May 1977 
Accepted 2 October 1977 



76 



The Canadian Field-Naturalist 



Vol. 92 



Prey Utilized by Merlins Nesting in Shortgrass Prairies 
of Southern Alberta 



Keith Hodson 

B.C. Fish and Wildlife Branch, Box 3250, Smithers, British Columbia V9J 2N0 

Hodson, Keith. 1978. Prey utilized by Merlins nesting in shortgrass prairies of southern Alberta. Canadian Field- 
Naturalist 92(1): 76-77. 



During the summers of 1969-1974 field investi- 
gations of Richardson's Merlin {Falco columbarius 
richardsonii) were conducted in southern Alberta 
(Hodson 1976). All Merlins discussed here were 
nesting in small clumps of poplar {Populus sp.) 
and/ or Manitoba maple {Acer negundo) adjacent to 
shortgrass {Stipa-Agropyron) prairie. Two abundant 
passerine birds of this habitat. Horned Larks 
{Eremophila alpestris) and Chestnut-collared Long- 
spurs (Calcarius ornatus) together formed 87% of 
prey during the nesting season. 

During field investigations a collection was made of 
2070 feathers (primary, secondary, and tail only), legs, 
and beaks of birds and skulls of rodents, and items 
were later identified. Although the numbers of 
individuals of each species could not be determined, 
the numbers of prey-remain items were high (i.e., 
many times the maximum from a single prey), and it is 
assumed that frequency of prey items is repre- 
sentative of comparative numbers of prey captured. 

I found that 50% of prey-remain items were from 
Horned Lark, 37% from Chestnut-collared Longspur, 
3% from Western Meadowlarks (Sturnus neglecta), 
2% from Vesper Sparrows {Pooecetes gramineus), 
and 8% from species of less than l%oftotal prey items 
(Table 1). Some species, such as Pine Siskins, are non- 
resident on the study area and were undoubtedly 
picked up during spring migration. A family of newly 
fledged Merlins was observed pursuing and eating 
grasshoppers after a heavy hatch of these insects (D. 
O'Dell, personal communication). In a similar study 
of Merlins in southern Saskatchewan, Fox (1964) 



found that the composition of prey remains was 53.5% 
Horned Larks, 13.6% Chestnut-collared Longspurs, 
13.3% Brown-headed Cowbirds {Molothrus ater), 
and 20.1% native sparrows. Chestnut-collared Long- 
spurs are basically birds of grasslands (Table 2) and 
the smaller amount of this species in prey remains 
from Merlins nesting in Saskatchewan could be 
explained by the small amounts of grassland left there. 
During the time of Fox's study in the early 1960s, 48% 
(range 28 to 89%) of the territory around 15 Merlin 
nesting sites was under cultivation; in comparison, 
only 22% (range to 49%) of territory around 40 
Merlin nesting sites I studied in southern Alberta in 
the early 1970s was under cultivation (Hodson 1976). 

In a fescue {Festuca) grassland in southern Alberta, 
Owens and Myres (1973) showed that breeding 
populations of passerine birds are more dense on 
grassland than on cultivated land (Table 2). My study 
area, though primarily Stipa-Agropyron prairie, was 
within a few miles of Owens', and populations of 
passerine birds were comparable both in density and 
species. My observations indicated that Merlins were 
hunting primarily over grasslands. 

Grasslands in my study area were mostly grazed 
(probably > 75%) but did include some mowed and 
undisturbed grasslands at some time of the year; most 
undisturbed grasslands in May-July were mown by 
the end of August. Species of grassland birds taken by 
Merlins would suggest that they are seldom utilizing 
undisturbed grasslands; Baird's Sparrow {Ammo- 
dramus bairdii) and Sprague's Pipit {Anthus sprag- 
ueii), the two most common passerines in undis- 



Table 1— Prey of Richardson's Merlins in southern Alberta, I969-I974, as determined by examination of 2070 prey- 
remain items found at 46 nest sites 



Prey item 



Prey present, 
% of nests 



Frequency 



Horned Lark {Eremophila alpestris) 
Chestnut-collared Longspur {Calcarius ornatus) 
Western Meadowlark {Sturnella neglecta) 
Vesper Sparrow {Pooecetes gramineus) 
Other species (4% unidentified passerines)^ 



100 
100 

< 10 

< 10 



50 

37 

3 

2 



'Trace species (less than 1%) include McCown's Longspur (Calcarius mccownii). Lark Bunting (Calamospiza melanocorys). Pine Siskin (Spinus pinus). Cedar 
Waxwing (Bombycilla cedrorum). Eastern Kingbird (Tyrannus lyrannus), Wilson's Phalarope (Sleganopus tricolor). Spotted Sandpiper (Aclitis macularia), 
unidentified shorebirds (Charadriiformes), Richardson's ground squirrel (juvenile) (Spermophilus richardsoni). other rodents (Cricetidae). 



1978 



Notes 



77 



Table 2 — Mean number of passerine pairs per 40 acres (16.4 ha) by land-use type (data from Owens and Myres 1973) 



Bird species 





Land- 


-use type 






Fescue 


grassland 




Cultivated land 


Undisturbed 


Mowed 


Grazed 


Seeded 


Fallow 


6.75 


0.00 


0.00 


0.00 


0.00 


9.50 


5.00 


0.00 


0.00 


0.00 


3.75 


1.00 


1.00 


0.00 


0.00 


1.00 


0.00 


1.00 


0.00 


0.00 


0.00 


10.00 


5.50 


0.00 


0.00 


0.75 


0.00 


1.00 


0.00 


0.00 


0.00 


0.00 


2.50 


2.00 


3.00 


0.00 


0.00 


0.00 


0.50 


0.00 


0.00 


0.50 


0.00 


0.00 


0.00 



Baird's Sparrow (Ammodramus bairdii) 
Sprague's Pipit (Anthus spragueii) 
Savannah Sparrow (Passerculus sandwichensis) 
Western Meadowlark {Sturnella neglecta) 
Chestnut-collared Longspur {Calcarius ornatus) 
Clay-colored Sparrow {Spizella pallida) 
Horned Lark {Eremophila alpestris) 
Vesper Sparrow {Pooecetes gramineus) 
Red-eyed Vireo ( Vireo olivaceus) 



turbed grasslands (Table 2), were not found at all in 
remains collected at Merlin nest sites. Undisturbed 
grasslands probably provided better escape cover for 
potential prey and thus were less productive for 
hunting Merlins. 

In a study of grassland bird communities in the 
Pawnee IBP Grassland Study Area in Montana, 
Wiens (1973) states "... the response of individual 
species to grazing effects was more clear-cut. Horned 
Lark density was greater in grazed plots and, at 
Pawnee, in plots subjected to heavy summer 
grazing . . .". The high percentage of Horned Larks 
found in the diet of Merlins seems to indicate the 
preference of Merlins for grazed land to hunt over. 
Owens (1973) found Horned Lark density high on 
grazed lands but insignificant on other grasslands, 
and higher only on fallow cultivated lands. Land 
under cultivation formed a significant portion of 
territory available for hunting Merlins (22% Hodson 
1976), and, although never observed, Merlins un- 
doubtedly utilized these areas as well. 

Heavy utiUzation of Horned Larks and Chestnut- 
collared Longspurs by Merlins may also be related to 
the behavior of these birds. Cody (1968) in his work on 
the Pawnee IBP Grassland Study Area devised a scale 
of feeding behavior for 14 North American species, 
and a graph depicting the distance moved over a given 
time span showed that the two most "active" species 
were Horned Larks and Chestnut-collared Long- 
spurs. Perhaps the more active feeding behavior of 
these birds makes them more noticeable to hunting 
Merlins. Owens (personal communication) has made 
the additional point that the height of aerial flight 
displays of some species of grassland birds may make 
them less available than other species by placing them 
out of the optimum altitude of hunting Merlins. 
Owens gives the heights of display of four species 
under consideration as these: Sprague's Pipit at 
300 m, Baird's Sparrow at ground level. Horned 
Larks at 60 m, and Chestnut-collared Longspurs at 
6 m. This mechanism would obviously operate only 



during breeding display periods of the particular 
grassland bird. 

In summary, I suggest that MerUns of southern 
Alberta living in shortgrass prairies are probably 
hunting mainly over grazed grassland where there is 
little escape cover for potential prey. Although less 
abundant on my study area, mowed grasslands or 
agricultural land in seed or fallow would fall in the 
same category. This is supported by the fact that 
Horned Larks and Chestnut-collared Longspurs, 
which were the most heavily utilized prey and were 
found in remain items at every nest site, are a very 
common passerine in these habitats and are not 
common elsewhere. The most abundant species of 
undisturbed grasslands were not utilized at all. 
Behavioral attributes of Horned Larks and Chestnut- 
collared Longspurs may also add to their preference 
as prey by Merlins. 

The study was conducted in conjunction with the 
pesticide monitoring program of the Canadian 
Wildlife Service's Toxic Chemical Section. Special 
thanks to Ken, Kip, and Kelly Fyfe and to Darren 
Ethier for their assistance. 

Literature Cited 

Cody, M. L. 1968. On the methods of resource division 
in grassland bird communities. American Naturahst 
102(924): 107-147. 

Fox, G. A. 1964. Notes on the western race of the Pigeon 
Hawk. Blue Jay 22(4): 140-147. 

Hodson, K. A. 1976. The ecology of Richardson's Merlin 
on the Canadian Prairies. M.Sc. thesis, University of 
British Columbia, Vancouver. 83 pp. 

Owens, R. A. and M. T. Myres. 1973. Effects of agri- 
culture upon populations of native passerine birds of an 
Alberta fescue grassland. Canadian Journal of Zoology 
51: 697-713. 

Wiens, J. A. 1973. Pattern and process in grassland bird 
communities. Ecological Monographs 43(2): 237-270. 

Received 18 August 1976 
Accepted 28 September 1977 



78 The Canadian Field-Naturalist Vol. 92 

Northern Leopard Frogs and Bullfrogs on Vancouver Island 



David M. Green 

Department of Zoology, University of Guelph, Guelph, Ontario NIG 2W1 

1978. Northern Leopard Frogs and Bullfrogs on Vancouver Island. Canadian Field-Naturalist 



Green, David M 
92(1): 78-79. 

Established feral populations of Northern Leopard 
Frogs, Rana pipiens, and Bullfrogs, R. catesbeiana, 
were found in the Parksville area of central Vancouver 
Island in the summer of 1976. According to C. Darkis 
of Qualicum Beach, British Columbia and C. Randall 
of Errington, British Columbia, these frogs were 
introduced to the drainage region of French Creek 
in the 1 930s as stock for a frog farm, and subsequently 
released. The source(s) of these stocks is not known. 
These are the first known occurrences of these species 
on Vancouver Island; they are not noted as occurring 
there in any previous literature (Stebbins 1954, 1966; 
Logier and Toner 1961; Carl 1966; Dumas 1966; 
Conant 1975). 

The dates and numbers of frogs seen in 1976 and 
1977 are listed in Table 1. Both adults and larvae of 
R. pipiens were seen on six occasions at Hamilton 
Swamp, a permanent beaver pond located 1.5 km 
northwest of Coombs, British Columbia and draining 
into French Creek. Transforming individuals were 
seen in late July. Four specimens (DMG 169 172), 
now preserved, were taken in August 1977. 



These frogs were identified as Rana pipiens, distinct 
from other members of the R. pipiens complex of 
species by the straight dorsolateral folds and lack of a 
distinct tympanal spot (Figure 1 ) as described by Pace 
(1974). In R. pipiens the dorsolateral folds are 
continuous and not displaced and. although some 
specimens show a slight constriction of the fold near 
the base, they are never broken nor displaced medially 
towards their posterior as in R. blairi and R. 
berlandeh. The distinct white spot on the tympanum 
seen in R. utricularia and most R. ^/a/r/ (Mecham et 
al. 1973) is absent in R. pipiens. This identification 
was corroborated by F. W. Schueler of the University 
of Toronto and J. P. Bogart of the University of 
Guelph. As no adult males were collected and no calls 
were heard, the shape of the vocal sacs, presence of 
vestigial oviducts, and mating call characteristics in 
these frogs could not be checked. 

In 1976, R. catesbeiana was observed at Dudley 
Swamp and in large numbers at Bell Lake (Table 1), 
two extensive beaver ponds near the village of 
Errington, British Columbia. Six adults were counted 



Table 1- 



-Sightings of frogs in the Parksville region of Vancouver Island in 1976 and 1977. Numbers of individuals 

observed are in brackets 



Locality 



Rana pipiens 



Rana catesbeiana 



Rana aurora 



Hamilton Swamp 



Bell Lake 

Dudley Swamp 

M. Wolfe's Farm 

Little Qualicum Falls 
Provincial Park 

Englishman River Falls 
Provincial Park 



6 June 1976 (3) 
17 June 1976 (1) 
26 June 1976 (4) 
29 Julv 1976 (2)*** 
12 Aug. 1976 (3) 
21 Apr. 1977 (2)** 
19 Aug. 1977 (4) 



6 June 


1976* 


6 June 


1976(5) 


20 Apr. 


1977 (1)** 


10 June 


1976(2) 


19 Aug. 


1977* 


23 Julv 


1976(1)*** 






29 Julv 


1976(4)*** 






12 Aug. 


1976 (2) 






23 Aug. 


1976 (2) 






19 Aug. 


1977 (2) 


16 Julv 


1976(100+) 


16 July 


1977 (1) 


18 July 


1976 (100+) 






21 Aug 


1976 (D* 






21 Aug 


1976 (6) 










1 Aug. 


1976 (7) 






5 Julv 


1976 (15) 






19 Aug 


1977 (3) 



* Calls heard. 

** Collected by F. W. Schueler. 

*** Transforming indi\iduals noted. 



1978 



Notes 



79 




Figure I. Immature female Northern Leopard Frog, Rana 
pipiem. (DMG 170) collected 19 August 1977 at 
Hamilton Swamp on Vancouver Island. 

in a small muddy pond at M. Wolfe's farm, Swayne 
Road, Errington. Calls only were heard at Hamilton 
Swamp in June 1976 and in August 1977. 

F. W. Schueler also collected road-killed specimens 
of R. pipiens (FWS7711) and R. catesbeiana 
(FWS 7709) near Hamilton Swamp, in April 1977. 
These are included in Table 1. 

These Bullfrog and Northern Leopard Frog popu- 
lations are far removed from any known previously. 
They are isolated on Vancouver Island, separated 
from the mainland by the Strait of Georgia. The 
nearest previous record of R. pipiens to Hamilton 
Swamp is at Osoyoos Lake in the Okanagan Valley 
(Carl 1949), roughly 400 km east. The nearest 
Bullfrogs are those introduced, and now common, 
across the strait in the lower Fraser Valley near 
Vancouver. With the Green Frog, R. clamitans, found 
at Victoria (Carl 1 966), there are now three introduced 
species of Rana recorded on Vancouver Island. 

It would be interesting to know in more detail how 
the two introduced species, R. pipens and R. 
catesbeiana, interact with the native Red-legged Frog, 
R. aurora. Although no detailed study was under- 
taken, R. aurora was seen in numbers about equal to 
those of R. pipiens at Hamilton Swamp (Table 1). At 
Bell Lake, however, with its substantial numbers of 
Bullfrogs, only one Red-legged Frog was seen. This 
may indicate that R. aurora and R. pipiens can coexist 
at Hamilton Swamp while being excluded from Bell 
Lake by R. catesbeiana. Comparable situations could 
be in the elimination of R. aurora and R. boylii irom 
the San Joaquin Valley in California by introduced 
Bullfrogs as discussed by Moyle (1973) or the 



competitive exclusion of R. pretiosa by R. pipiens in 
Oregon as discussed by Dumas (1964). The threat of 
elimination of R. aurora from central Vancouver 
Island by Northern Leopard Frogs and Bullfrogs is 
probably not severe, however. I have observed Red- 
legged Frogs to be quite common along forest streams 
in nearby areas such as Englishman River Falls 
Provincial Park and Little Qualicum Falls Provincial 
Park (Table 1). There is an abundance of such forest 
habitat for the Red-legged Frogs that is unsuitable for 
colonization by the other two species. 

Photographs taken in 1976 and those specimens 
collected by F. W. Schueler are at the National 
Museum of Natural Sciences. The four specimens 
collected 19 August 1977 are in the author's 
possession. 

1 thank J. P. Bogart for his help, F.W. Schueler 
for additional information, and F. R. Cook for his 
comments. 



Literature Cited 

Carl, G. C. 1949. Extensions of known ranges of some 

amphibians in British Columbia. Herpetologica 

5: 139-140. 
Carl, G. C. 1966. The amphibians of British Columbia. 

Handbook Number 2 British Columbia Provincial 

Museum, Victoria, pp. 1-62. 
Conant, R. 1975. A field guide to reptiles and amphibians 

of eastern and central North America. Houghton Mifflin 

Co., Boston. 429 pp. 
Dumas, P. C. 1964. Species pair allopatry in the genera 

Rana 2LX\d Phrynosoma. Ecology 45: 178-181. 
Dumas, P. C. 1966. Studies of the Rana species complex 

in the Pacific Northwest. Copeia 1966: 60-74. 
Logier, E. B. S. and G. C. Toner. 1961. Checklist of the 

amphibians and reptiles of Canada and Alaska. Life 

Sciences Division, Contribution Number 53, Royal 

Ontario Museum, pp. 1-92. 
Mecham, J. .S., M. J. Littlejohn, R. S. Oldham, L. E. 

Brown, and J. L. Brown. 1973. A new species of leopard 

frog {Rana pipiens complex) from the plains of the 

central United States. Occasional Papers of the Museum 

of Texas Tech University 18: 1-11. 
Moyle, P. B. 1973. Effects of introduced Bullfrogs, Rana 

catesbeiana, on the native frogs of the San Joaquin 

Valley. California. Copeia 1973: 18-21. 
Pace, A. E. 1974. Systematic and biological studies of 

leopard frogs (Rana pipiens complex) of the United 

States. Miscellaneous Publications of the Museum of 

Zoology, University of Michigan Number 148. pp. 1-140. 
Stebbins, R. C. 1954. Amphibians and reptiles of western 

North America. McGraw-Hill Book Co. Inc., New York. 

536 pp. 
Stebbins, R. C. 1966. A field guide to western reptiles 

and amphibians. Houghton Mifflin Co., Boston. 279 pp. 



Received 21 January 1977 
Accepted 21 November 1977 



80 



The Canadian Field-Naturalist 



Vol. 92 



Northern Fulmar Breeding Range Extended to Baccalieu Island, 
Newfoundland 



W. A. MoNTEVECCHi,' E. Blundon,^ G. Coombes, J. PoRTER,3 and p. RlCE^ 

'Department of Psychology, memorial University of Newfoundland, St. John's, Newfoundland AlC 5S7 

-Bay de Verde, Newfoundland 

-^Department of Biology, Acadia University, Wolfville, Nova Scotia 

''Red Head Cove, Newfoundland 

Montevecchi, W. A., E. Blundon, G. Coombes, J. Porter, and P. Rice. 1978. Northern Fulmar breeding range extended to 
Baccalieu Island, Newfoundland. Canadian Field-Naturalist 92(1): 80-82. 

Gulch on the northeast end of BaccaUeu Island 
(48°07'N, 54°I2'W) we sighted five single, light- 
phased fulmars sitting on ledges (Figure 1); two sites 
that we could see from the cliff top each had an egg. 
On 10 August a chick, judged to be 3^ weeks 
posthatch, was found; the other site where the egg had 
been within our reach was empty. Some evidence 
suggested that predation or predatory disturbance 
may have been involved. A decapitated, eviscerated 
adult Northern Fulmar was found nearby on 1 1 June, 
and there were signs of Red Fox {Vulpes vulpes) 
activity (digging at Leach's Storm-Petrel {Oceano- 
droma leucorhoa) burrows; dead petrel chick) in the 
area. 



The numbers of Northern Fulmars {Fulmarus 
glacialis) have been increasing in the boreal regions of 
the Northeast Atlantic for more than two centuries, 
and though population growth appears to have 
slowed recently (Fisher 1952, 1966; Salomonsen 1965) 
the breeding range of the species continues to expand. 
In the past few years Northern Fulmars have been 
found breeding in two locations off Newfoundland: 
Great Island (47° ll'N, 52°49'W) in Witless Bay 
(Nettleship and Montgomerie 1974) and Funk Island 
(49°46'N, 54°12'W), as documented in Nettleship's 
recent (1976) film, "The Funks." 

During visits by land and boat on 27 May, 1 and 
11 June 1977, to the cliffs just south of Jackson's 




Figure 1. Incubating Northern Fulmar on a ledge near the top of a cliff on Baccalieu Island, 27 May 1977. 



1978 



Notes 




Figure 2. Newly hatched Northern Fulmar on Funk Island, 10 July 1977. 



Four pairs of fulmars were seen occupying four 
cliff-ledge sites on 1,3, and 8 June in Bull Gulch just 
north of Gannet Head on the east side of the island 
about 1.5 km south of Jackson Gulch. No fulmars 
were seen in this area from 7 to 12 August. The 
behavior and temporary site tenacity of these birds 
suggested they were "prospecting" (Fisher 1952; 
Nettleship and Lock 1973). Northern Fulmars have 
been observed on Baccalieu Island as long ago as 1959 
(Rice). Future checks on colonization in this area will 
be made. 

On 9-10 July 1977 Montevecchi and Porter found 
three fulmars with eggs on Funk Island, two nesting 
on flat ground, the other on a ledge about 1 .5 m above 
ground. In the two nests checked, one egg hatched on 
10 July (Figure 2), the other pipped on 11 July, 
indicating that egg-laying occurred toward the end of 
May. This is consistent with the timing of egg-laying 
on Baccalieu and in the boreal North Atlantic in 
general (Fisher 1952). 

Baccalieu Island is the third island off New- 
foundland where Northern Fulmars have been found 
breeding in 4 years, and breeding attempts in 
Labrador (Nettleship and Lock 1973) and along the 
Avalon Peninsula of Newfoundland (L.M. Tuck, 
personal communication) seem likely. The Northern 
Fulmars' potential for massive and sustained popu- 



lation increase as evidenced at colonies in Great 
Britain during the past and present centuries (Fisher 
1952) leaves open the possibility that we may be 
witnessing the initial stages of what may soon be a 
population explosion of the species in the boreal 
Atlantic regions of Canada. Close watch should be 
kept for further breeding range expansion of these 
birds, and breeding censuses at known nesting areas 
should be made regularly. The light-phase plumage of 
all Northern Fulmars found nesting or "prospecting" 
in Newfoundland-Labrador suggests that these birds 
may be immigrating from colonies in western Green- 
land, Iceland, or Great Britain (Fisher 1952; Salo- 
monsen 1965; Brown 1970; Tuck 1971) rather than 
from the Canadian arctic region. Banding data 
and/ or body (especially culmen) measurements 
(Salomonsen 1965) may help clarify this matter in the 
future. 

We are grateful to the Newfoundland Wildlife 
Division and the Canadian Wildlife Service for 
permission to work in these locations, to Bruce Bursey 
and Dr. Leslie M. Tuck for helpful suggestions, and to 
Raymond Hyde, Felix Noonan, and Linus Walsh for 
their hospitality on Baccalieu Island. Financial 
support was provided by National Research Council 
of Canada Grant No. A0687 awarded to W. A. 
Montevecchi. 



82 



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Vol. 92 



Literature Cited 

Brown, R. G. B. 1970. Fulmar distribution: a Canadian 
perspective. Ibis 111: 44-51. 

Fisher, J. 1952. The Fulmar. Collins, London. 

Fisher, J. 1966. The Fulmar population of Britain and 
Ireland, 1959. Bird Study 13: 5-76. 

Nettleship, D.N. and A. R. Lock. 1973. Observations of 
Fulmars on ledges in Labrador. Canadian Field-Natura- 
list 87: 314. 

Nettleship, D. N. and R. D. Montgomerie. 1974. The 
Northern Fulmar, Fulmarus glacialis, breeding in 



Newfoundland. American Birds 28: 16. 
Salomonsen, F. 1965. The geographical variation of the 

Fulmar {Fulmarus glacialis) and the zones of marine 

environment in the North Atlantic. Auk 82: 327-355. 
Tuck, L. M. 1971. The occurrence of Greenland and 

European birds in Newfoundland. Bird-Banding 42: 

184-209. 



Received 15 September 1977 
Accepted 21 October 1977 



Life History Observations on the Nudibranch Mollusc Onchidoris 
bilamellata in the Intertidal Zone of Nova Scotia 

J. Sherman Bleakney and Constance L. Saunders 

Department of Biology, Acadia University, Wolfville, Nova Scotia BOP 1X0 

Bleakney, J. Sherman and Constance L. Saunders. 1978. Life history observations on the nudibranch mollusc Onchidoris 
bilamellata in the intertidal zone of Nova Scotia. Canadian Field-Naturalist 92(1); 82-85. 

Analysis of Nova Scotia collections of the nudibranch Onchidoris bilamellata (L., 1767) from 1967 to 1977 
demonstrates an annual die-off of the adult population between May and July. This is also observed in European populations 
of this species. Spawning normally extends from January to May but juveniles could not be found before late July or August. 

Key Words: dorid nudibranch, Onchidoris bilamellata, life history, annual species. Nova Scotia, Minas Basin. 



Dorid nudibranchs are carnivorous gastropod 
molluscs found in a great variety of marine habitats. 
Onchidoris bilamellata (L., 1767) is a seasonally 
common intertidal species of rocky shores, where it 
preys upon Balanus balanoides and other species of 
barnacles. It is a widely distributed species of boreal 
and sub-arctic seas of the Northern Hemisphere with 
a northern limit near 70° N. On the European coast it 
appears as far south as Sandgate, South Kent, 
England, and at Winereux, Pat de Calais, France. 
Along the northwest Atlantic shores Connecticut is 
evidently the southern limit. 

This dorid is evidently an annual and the adults 
reportedly die in early summer after spawning. 
Therefore, it is rarely encountered in summer when 
field survey crews are most active. As the basic life 
history of this major winter predator of barnacles has 
been investigated only in England, our Nova Scotia 
data represent the first comparative study of popula- 
tions from the western Atlantic. 

Recent literature includes distributional reports 
from the northeast and northwest Atlantic coasts 
(Miller 1961; Swennen 1961; Franz 1970; Potts 
1970; Meyer 1971). The life cycle of O. bilamellata in 
Europe, however, has been studied only in England 
and that was based on data from fewer than 3 years, 
1964-1966 (Potts 1970). Clark (1975) described the 



life cycles of 24 species of Atlantic nudibranchs, 
including O. bilamellata, based on 4 years of 
observation of the Connecticut fauna. Unfortunately 
this species is rare at that latitude and Clark's data are 
inadequate for critical comparison with those of Potts 
and the present study. The seasonal occurrence of O. 
bilamellata on the Pacific coast of Washington State 
was mentioned incidentally by Connell (1970) and 
Dayton (1971) in connection with their Balanus 
studies. 

Study Areas 

Our collections are from Annapolis and Kings 
Counties, Nova Scotia, particularly along the western 
shores of the Minas Basin area (Figure 1). The Bay of 
Fundy coast of southwestern Nova Scotia is com- 
posed of basalt, an ideal substrate for barnacles, and 
rocks from this ridge are scattered over the sandstone, 
sands, and muds of the extensive eulittoral zone of the 
Minas Basin and Annapolis Basin. The most con- 
spicuous and consistently present barnacle predator 
on these rocks is the dogwinkle Nucella lapillus. 
Purple and white varieties of the predaceous dorid 
Acanthodoris pilosa are often associated with O. 
bilamellata, but they are feeding solely upon the 
encrusting ectoproct colonies of Alcyonidium 
polyoum. More extensive descriptions of the two 



1978 



Notes 



83 




Figure 1. Map of the six areas in Annapolis and Kings 
Counties where Onchidoris bilamellata was collected. 
Major sites are 1, Cape Blomidon; 2, Kingsport; and 
3, Black Rock. Of lesser importance were 4, Port 
George; 5, Hampton; and 6, Port Royal. 

Minas Basin study sites. Cape Blomidon and Kings- 
port, have been published previously (Bleakney and 
McAllister 1973; Bleakney and Mustard 1974). 

Methods 

Our general collections of nudibranchs taken at 
extreme low tides were begun on a year-round basis in 
1967, although the annual emphasis varied relative to 
species and habitats. Table 1 summarizes a 10-year 
accumulation of observations of bilamellata. 

During field excursions, populations of O. bilamel- 
lata were often observed but not collected particularly 
if we already had data from that time period. Thus the 
many blanks in Table 1 do not necessarily indicate the 
species' absence nor a cessation of field activities for 
that month. Only representative size-range samples 



were collected because any regular intensive collecting 
aimed at determination of population size-class 
changes could decimate local restricted populations. 
At any one time most individuals were similar in size 
and after collecting several of these efforts were 
concentrated on finding any larger or smaller speci- 
mens. This size range information, based on 58 
collections totalling 453 specimens, is presented in 
Figure 2. 

Results and Discussion 

It is evident from the information provided by Potts 
(1970) and by our observations in Nova Scotia, that 
O. bilamellata is an annual species but the basic 
pattern is not rigidly fitted to calendar months. For 
example. Potts determined that in 1964 the adults 
were absent from 10 May to 30 July but in 1965 they 
were absent for a 6-month period from 29 April to 16 
October. Similarly, in Nova Scotia 1969 was excep- 
tional. Spawn from this species has been found in all 
months from January through July (Figure 2), but on 
1 6 field trips in June and July only in 1 969 were adults 
and/ or spawn found (once in June and three times in 
July). Apparently on both sides of the Atlantic egg 
laying is concentrated in the cold-water months of 
January through April but remarkably the species is 
capable of living and spawning on into July, at least in 
the Minas Basin. Meyer (1971) failed to find O. 
bilamellata along the coast of Nova Scotia in June and 
July of 1968, except at Kingsport, Minas Basin. (Date 
of capture and size of specimens were not reported.) 
Data on growth and on spawning in Washington 
State are lacking but the species has been observed 
intertidally only from September to March (Dayton 
1971). 

In England the smallest individuals were found in 
July and August (Potts 1970), while in Nova Scotia 
they were found in August and September. On the 



Table 1 — Distribution of 73 documented field trips by year and month in search of Onchidoris bilamellata in Kings and 
Annapolis Counties, Nova Scotia. Inclusive unproductive trips are bracketed. The 58 collections contained 453 specimens 



Year 



Trips/ 



Months 



M 



M 



O 



N 



D 



1967 2 

1968 3 

1969 12 

1970 12 

1971 4 

1972 2 

1973 -4 

1974 4 

1975 3 

1976 - 20 

1977 7 
Total trips 

Total specimens collected 



_________ 2 1 — 

1 1 — — 2 3(2) 4(2) _ _ 1 _ _ 

1 2(1) 2— — — — 3 1 — 2 1 

— 2 1 ______ l__ 

__________ 2(1) - 

__1_2— — — — — 1 — 

_ 1 _____(!)_ 1 __ 

— 1 2 — 1 3(3) 4(3) 3 2 3 1 — 

— 11 — 1 1(1) 1(1) 1 1 

4 8(1) 7 1 7 7(6) 9(6) 7(1) 4 10 7(1) 1 

10 25 73 30 30 1 1 63 73 1 1 1 27 



84 



The Canadian Field-Naturalist 



Vol. 92 



30 



25 



20 - 



15 - 



10 



5 - 



-1 I I I I 




****** ^- spawn 
' ' 



A 


M 


J 


J 


A 


S 





N 


D 





30 





30 


11 


63 


73 


111 


27 



month J F M 
totals 10 25 73 

Figure 2. A monthly summary of size range distribution of 
the largest (upper graph) and smaller (lower graph) 
individuals of Onchidoris hilamellata collected in 
Nova Scotia from 1967 to 1977. For each month there 
is an upper set of lines showing the size range of the 
largest individuals from every collection over this 
time period, and below is a similar vertical line 
showing the size range of the smallest individuals 
from the same collections. Note that in 1969 the July 
population consisted of adults whereas onlyjuveniles 
were present in 1976. There is an evident annual 
population die-off of adults from May to July. 

Pacific coast small individuals invaded screened 
barnacle cages only between September and Decem- 
ber (Connell 1970), again indicating an annual 
recruitment of juveniles. 

Individuals apparently grow rather rapidly, for 
Nova Scotia collections from October and November 
have specimens of maximum size. In November 1968 
and 1970, February 1969, and October 1969, maxima 
near 30 mm were noted. This is 5-7 mm larger than 
most of Potts' 613 British specimens. These large 



individuals could well be peculiar to those years, as 
we have noticed that other species of nudibranchs 
(and sacoglossans) may sporadically produce popula- 
tions of mega-individuals. It is evident from examina- 
tion of Figure 2, that over a 10-year period the size 
range in any one month can vary considerably within 
the two categories of largest and smallest individuals. 
This could be the result of increased or decreased 
growth rate for that year or an earlier or later 
recruitment of juveniles. July 1969 was unusual in that 
large spawning adults were still active in Minas Basin. 
Sampling the same areas in July 1976 yielded only 
juveniles. 

Potts and Clark failed to emphasize both the 
peculiar and the enigmatic aspects of reproduction in 
O. bilamellata. First, the species must grow to near 
maximum size before spawning (Potts 1970). This is 
peculiar because many other opisthobranchs spawn at 
sizes of only several millimetres and continue to 
spawn as they increase in size. Second, the fate of the 
veligers that hatch from December through May is an 
enigma. Hadfield (1963) was determined that hatching 
(near Denmark) takes about 8-9 days and the free 
swimming veliger larval stage can be extended in the 
laboratory for 32 days. Clark (1975) listed eight cold- 
water species including O. bilamellata appearing in 
Connecticut that have an interval of at least 5 months 
between disappearance of the adults and the first 
appearance of the juveniles. He concluded that local 
populations were not self-sustaining, but received a 
periodic influx of larvae from further north where 
populations are probably present most of the year. 
Our evidence from Nova Scotia and England does not 
support his assumption of nearly year-round larval 
production farther north. Potts concluded that 
juveniles in his area in England might be recruited 
from some distant population and stated that in spite 
of the long breeding season, only eggs laid towards the 
end of that season were likely to be of any value in the 
recruitment of the next population. Unfortunately, 
the maximum free-living veliger larval period is not 
known, but any period longer than 2 months seems 
unreasonable in the light of Hadfield's experiments. 
Yet the Nova Scotia and British collections demon- 
strate an absence of juveniles until 8 months after the 
first eggs are laid. 

Remarks 

Rather than attempt speculative conclusions, we 
feel obliged to state pertinent questions. Why does the 
characteristic early winter spawning persist year after 
year if there are no survivors from this genetic 
component of the population? Why are the minimal 
juvenile size classes of 2-5 mm in Nova Scotia and 
England found only in July, August, and September? 
Why is there such a range in body length from 5 to 



1978 



Notes 



85 



30 mm in November in Nova Scotia if these in- 
dividuals are from the same invasive recruitment of 
August or September? If they represent an invasion 
from an offshore deep-water winter population then 
many should have 6 to 8 months growth by August. 
Why should the winter juveniles restrict themselves to 
offshore waters from January to August when most of 
the population is in the intertidal balanoid zone? 

On the evidence from both sides of the Atlantic one 
can conclude, albeit unreasonably, that after 6 months 
of spawning the entire population of adults and 
juveniles dies out in May or June only to be replaced 
60-90 days later in August and September by 
individuals 2 to 5 mm long. Although O. bilamellata is 
a common amphiatlantic boreal dorid nudibranch 
and has been neatly categorized as an annual species, 
it exhibits an enigmatic recruitment pattern. 

The National Research Council of Canada (Grant 
A2009) provided the basic funding for our long-term 
molluscan studies. 

Literature Cited 

Bleakney, J. S. and D. E. McAllister. 1973. Fishes 
stranded during extreme low tides in Minas Basin, Nova 
Scotia. Canadian Field-Naturalist 87(4): 371-376. 

Bleakney, J. Sherman and Mary E. Mustard. 1974. 
Sponges of Minas Basin, Nova Scotia. Canadian Field- 
Naturalist 88(1): 93-95. 

Clark, K. B. 1975. Nudibranch life cycles in the Northwest 



Atlantic and their relationship to the ecology of fouling 
communities. Helgolaender Wissenschaftliche Meeresun- 
tersuchengen 27: 28-69. 

Connell, Joseph H. 1970. A predator-prey system in the 
marine intertidal region. I. Balanus glandula and several 
predatory species of Thais. Ecological Monographs 40( 1): 
49-78. 

Dayton, Paul K. 1971. Competition, disturbance and com- 
munity organization: The provision and subsequent 
utilization of space in the rocky intertidal community. 
Ecological Monographs 41: 351-389. 

Franz, D. R. 1970. Zoogeography of Northwest Atlantic 
opisthobranch molluscs. Marine Biology 7(2): 171-180. 

Hadfield, M. G. 1963. The biology of nudibranch larvae. 
Oikos 14(1): 85-95. 

Meyer, K.B. 1971. Distribution of and zoogeography of 
fourteen species of nudibranchs of northern New England 
and Nova Scotia. Veliger 14(2): 137-152. 

Miller, M. C. 1961. Distribution and food of the nudi- 
branchiate mollusca of the south of the Isle of Man. 
Journal of Animal Ecology 30: 95-116. 

Potts, G. W. 1970. The ecology of Onchidoris fusca 
(Nudibranchia). Journal of the Marine Biological 
Association of the United Kingdom 50(2): 269-292. 

Swennen, C. 1961. Data on distribution, reproduction and 
ecology of nudibranchiate molluscs occurring in the 
Netherlands. Netherlands Journal of Sea Research 1961: 
1191-1240. 

Received 27 June 1977 
Accepted 20 November 1977 



Additions to the Flora of Alberta and New Records 

Sylvester Smoliak and Alexander Johnston 

Research Station, Agriculture Canada, Lethbridge, Alberta TIJ 431 

Smoliak, Sylvester and Alexander Johnson. 1978. Additions to the flora of Alberta and new records. Canadian Field- 
Naturalist 92(1): 85-89. 

A list of 70 vascular plant species collected in southern Alberta is presented to amend Moss' Flora of Alberta. The list includes 
plants not listed by Moss or those he listed as being rare or expected in the area. 

Key Words: Alberta flora, new additions, new records. 



The standard taxonomic reference text in Alberta is 
E. H. Moss' Flora of Alberta. Since its appearance in 
1959, studies of the flora of the province have 
increased considerably, notably at the Universities of 
Alberta, Calgary, and Lethbridge and at the 
Lethbridge Research Station of Agriculture Canada. 

At the Lethbridge Research Station, the develop- 
ment and maintenance of a herbarium is the 
responsibility of range management specialists who 
use the herbarium for range inventories. Range 
inventories are basic to land-use planning and must 



adequately describe and evaluate resources to allow 
determination of the capability of the land to support 
livestock and wildlife and to identify areas of critical 
environmental concern. 

A key to the preparation of an inventory of 
rangeland is the vegetation, and a good range 
inventory showing the plant species, soils, geographic 
conditions, and rainfall is essential in determining the 
numbers of livestock that can be supported on any 
range. 

Since 1959, the herbarium collection at the 



86 



The Canadian Field-Naturalist 



Vol. 92 



Lethbridge Research Station has nearly doubled. 
Collectors during the period included T. D. Allen, G. 
Bohus, R. G. Gschaid, A. Johnston, J. J. Sexsmith, 
and S. Smoliak. The herbarium collections generally 
have been limited to the flora of southern Alberta. 

The herbarium contains 6848 specimens repre- 
senting 99 famiUes, 463 genera, and 1033 species. The 
systematic arrangement of the herbarium, following 
the numbering system of Rydberg (1932), provided an 
opportunity to itemize the collections on computer 
cards and tape. The computerized printout is used to 
provide an updated inventory of the herbarium. It has 
also enabled us to compare the contents of the 
Lethbridge Research Station herbarium with species 
described in the Flora of Alberta (Moss 1959). 

The voucher specimens of the additions listed below 
are retained in the herbarium at the Lethbridge 
Research Station. Some additional specimens are also 
deposited in the herbarium of Agriculture Canada, 
Biosystematics Research Institute, Ottawa. Most of 
the 70 species listed have been identified or verified by 
the personnel of the Cultivated Crop and the Noxious 
and Native Plant Sections, Biosystematics Research 
Institute, Ottawa, and are listed by Boivin(1967, 1969, 
1972) as occurring in Alberta. The nomenclature 
follows that of Boivin (1967, 1969, 1972) or in some 
instances Hitchcock and Conquist (1973). The native 
species are marked with an asterisk. 

The following abbreviations have been used in the 
listing: LRS, Lethbridge Research Station; MRS, 
Manyberries Research Substation; SRS, Stavely 
Research Substation. 

Species List 

GRAMINEAE 

Agropyron desertorum Fisch. 

MRS. Roadsides. 25 June 1973. Gschaid, Smoliak, and 

Allen 2854. 

Not previously reported for Alberta. 
Agropyron elongatum (Host) Beauv. 

LRS. Irrigated areas. 7 August 1973. Allen 2975. 

Not previously reported for Alberta. 
Agropyron trichophorum (Link) Richt. 

MRS. Roadside. 27 June 1973. Smoliak and Gschaid 

2860. 

Not previously reported for Alberta. 
Elymus angustus Trin. 

MRS. Dryland. 27 June 1973. Smoliak and Gschaid 

2861. 

Not previously reported for Alberta. 
Elymus junceus Fisch. 

MRS. Roadsides. 9 June 1948. Hubbard 1369. 

LRS. Dryland, 18 August 1969. Allen 2463. 

MRS. Fields and roadsides. 31 May 1972. Gschaid 

and Allen 2699. 

Not previously reported for Alberta. 
Lolium temulentum L. 
- Edmonton. Garden. 8 September 1938. Sexsmith 1 153. 



Foremost. Roadside. 3 July 1975. Coukell 3251. 

Not previously reported for Alberta. 
Panicum capillare L.* 

Brooks. Shore of Lake Newell. 19 September 1973. 

Smoliak, Gschaid, and Allen 3032. 

Not previously reported for Alberta. 
Poa nevadensis Vasey* 

MRS. Moist coulee. 19 June 1973. Smoliak, Gschaid, 

and Allen 2851. 

Not previously reported for Alberta. 
Puccinellia cusickii Weath.* 

MRS. Moist coulee. 19 June 1973. Smoliak, Gschaid, 

and Allen 2852. 

Not previously reported for Alberta. 
Sorghum vulgare Pers. 

LRS. Irrigated land. 14 August 1940. Peake 1223. 

Not previously reported for Alberta. 

LILIACEAE 
Asparagus officinalis L. 

Lethbridge. Oldman River valley. 18 August 1971. 

Gschaid and Allen 2673. 

Not previously reported for Alberta. 

SALICACEAE 

Salix fluviatilis Nutt.* 

MRS. Near dam. 1 8 May 1973. Gschaid and Allen 2838. 

Raymond. Near irrigation canal. 16 July 1973. Bohus 

2903. 

MRS. Roadside ditch. 5 September 1973. Smoliak, 

Gschaid, and Allen 3037. 

Reported by Boivin (1967). 

CANNABINACEAE 

Cannabis sativa L. 

Lethbridge. No location. August 1938. Peake 1138. 
Reported by Boivin (1967). 

POLYGONACEAE 

Fagropyrum esculentum Moench 

Lethbridge. No location. September 1917. Hirst 72. 

Reported by Boivin (1969). 
Polygonum erectum L.* 

Bow Island. Sandy area. 17 July 1967. Allen and 

Gschaid 2125. 

Reported by Boivin (1969). 
Rumex crispus L. 

Raymond. Irrigation canal. 16 July 1973. Bohus 2905. 

Not common in Alberta (Moss 1959). Reported by 

Boivin (1969). 

CHENOPODIACEAE 

Atriplex heterosperma Bunge 

Walsh. Alkaline area. 26 June 1969. Gschaid and Allen 

2398. 

Reported by Frankton and Bassett (1968). 
Atriplex oblongifolia Waldst. et Kit 

Lethbridge. Oldman River valley. 30 August 1971. 

Gschaid and Allen 2676. 

Not previously reported for Alberta. 
Atriplex powellii Wats.* 

Reported by Boivin (1969) and Frankton and Bassett 

(1970). 
Atriplex truncata (Torr.) Gray* 

Reported by Frankton and Bassett (1970). 



1978 



Notes 



87 



NYCTAGINACEAE 

Abronia micrantha Torr.* 

MRS. Sandy area. 19 July 1977. Smoliak 3462. 
Reported by Boivin(1967) and Johnson and Hallworth 
(1975). 

CARYOPHYLLACEAE 

Cerastium fontanum Baumg. subsp. mv/a/e(Murb.) Jalas 

West Castle. Gravelly roadside. 27 May 1969. Smoliak, 

Gschaid, and Allen 2347. 

Not previously reported for Alberta. 
Saponaria officinalis L. 

Lethbridge. Dry roadside. 14 August 1972. Gschaid and 

Allen 2750. 

Lethbridge. Oldman River valley. 19 August 1972. 

Allen 2750a. 

Carmangay. Roadside. 15 July 1976. Gschaid and 

Kesler 3417. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1969). 

RANUNCULACEAE 

Myosurus aristata Benth. subsp. montanus (Campbell) 
Stone* 

MRS. Alkaline slough. 8 June 1937. Campbell 1974. 

MRS. Slough edge. 3 May 1964. Smoliak 1929. 

MRS. Dry creek bed. 10 July 1967. Allen and Gschaid 

2126. 

Not common in Alberta (Moss 1959). 

CRUCIFERAE 

Alyssum desertorum Stapf 

Winnifred. Alfalfa field. 8 May 1968. Sexsmith 2174. 

Lundbreck Falls. Gravelly area. 14 May 1969. Allen 

and Gschaid 2356. 

Reported by Boivin (1969). 
Arabis microphylla Nutt.* 

Magrath. Bromegrass field. 14 July 1963. Allen and 

Johnston 1917. 

Not previously reported for Alberta. 
Barbarea vulgaris R. Br. 

Oliver. Roadside meadow. 5 June 1938. Sexsmith 1065. 

Not common in Alberta (Moss 1959). 
Brassica nigra (L.) Koch 

Lethbridge. Six Mile Coulee. 26 July 1971. Allen and 

Gschaid 2650. 

Expected in Alberta (Moss 1959). 

Lepidium latifolium L. 

Magrath. No location. 20 June 1932. No name 542. 

Lethbridge. Slough edge. 10 August 1951. Hobbs 1532. 

Raymond. Roadside. 1 August 1967. Allen and Gschaid 

2157. 

Stewart. Fields and roadsides. 31 July 1970. Smoliak 

and Allen 2515. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1969). 
Raphanus raphanistrum L. 

Pincher Creek. Moist ditch. 11 July 1972. Gschaid 

and Allen 2756. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1969). 

SAXIFRAGACEAE 

Conimetella williamsii (Eaton) Rydb.* 



Bobs Creek. Woods. 28 July 1973. Allen 2918. 
Reported by Boivin (1969) and Packer and Dumais 
(1972). 

LEGUMINOSAE 

Astragalus cicer L. 

LRS. Irrigated plot area. 15 July 1941. Johnston 1289. 

MRS. Irrigated field. 30 July 1948. Hubbard 1391. 

LRS. Roadside. 11 July 1973. Gschaid and Allen 293 1. 

MRS. Cultivated area. 5 September 1973. Gschaid, 

Smoliak, and Allen 3050. 

LRS. Machine yard. 2 July 1974. Bohus 3148. 
Astragalus falcatus Lam. 

LRS. Irrigated plot area. 5 August 1975. Smoliak 

3325. 

Not previously reported for Alberta. 
Lotus corniculatus L. 

LRS. Roadside. 1 1 July 1973. Gschaid and Allen 2928. 

Lethbridge. Waste area. 21 June 1974. Bohus 3113. 

Reported by Boivin (1967). 
Onobrychis viciaefolia Scop. 

LRS. Dryland plot area. 20 July 1917. Hirst 47. 

LRS. Waste area. 2 July 1974. Bohus 3149. 

Not previously reported for Alberta. 
Ornithopus roseus Duf. 

Edmonton. Garden. 8 September 1938. Sexsmith 1158. 

Not previously reported for Alberta. 
Trifolium agrarium L. 

Waterton Lakes National Park. Moist roadside. 8 July 

1969. Allen 2448. 

Allison Lake. Lake shore. 20 July 1970. Allan and Allen 

2521. 

Pincher Creek. Roadside. 6 July 1973. Smoliak, 

Gschaid, and Allen 2924. 

Very rare in Alberta (Moss 1959). Reported by Boivin 

(1967). 
Trifolium fragiferum L. 

Edmonton. University farm. 31 August 1938. Sexsmith 

1142. 

Lethbridge. Six Mile Coulee. 26 July 1971. Allen and 

Gschaid 2656. 

Not previously reported for Alberta. 
Trifolium procumbens L. 

Edmonton. University farm. 31 August 1938. Sexsmith 

1141. 

Edmonton. Railway embankment. 12 September 1938. 

Sexsmith 1 157. 

Reported by Boivin (1967). 
Trigonella coerulea (L.) Ser. 

Lethbridge. Irrigated field. 13 July 1938. Sexsmith 

1115. 

Reported by Boivin (1967). 

GERANIACAE 

Erodium cicutarium (L.) L'Her 

Raymond. Dryland. 10 August 1937. Sexsmith 1033. 

Raymond. Newly seeded field. 7 August 1970. King 

2562. 

LRS. Irrigated plot area. 28 June 1974. Bohus and 

Dalton 3120. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1972). 



The Canadian Field-Naturalist 



Vol. 92 



OXALIDACEAE 

Oxalis corniculata L. 
LRS. Greenhouse. 13 March 1975. Bohus 3184. 
Reported by Boivin (1972) and Packer and Dumais 
(1972). 

ZYGOPHYLLACEAE 

Zygophyllum fabago L. 

LRS. Irrigated plot area. 12 August 1968. Hanna2307. 

LRS. Irrigated plot area. 15 September 1968. Hanna 

2325. 

Not previously reported for Alberta. 

EUPHORBIACEAE 

Euphorbia peplus L. 

Raymond. Garden. 27 September 1974. Bohus 3178. 
Not previously reported for Alberta. 

VIOLACEAE 

Viola cucullata Ait.* 
SRS. Moist coulee. 14 May 1971. Allen 2595. 
Reported by Boivin (1967). 

UMBELLIFERAE 

Anethum graveolens L. 

Lethbridge. Waste areas and back alleys. 1 1 July 1971. 

Allen 2626. 

Reported by Boivin (1967) and Packer and Dumais 

(1972). 

ERICACEAE 

Menziesia ferruginea Smith* 

Racehorse Creek. Open woods. 6 June 1969. Allen and 

Johnston 2427. 

Reported by Boivin (1967). 

CONVOLVULACEAE 

Cuscuta umbrosa Hook.* 
Lethbridge. Oldman River valley. 30 August 1971. 
Gschaid and Allen 2680. 

Apparently rare in Alberta (Moss 1959). Reported by 
Boivin (1972). 

BORAGINACEAE 

Symphytum officinale L. 

LRS. Irrigated plot area. 25 June 1973. Allen 2889. 
LRS. Irrigated pasture area. 18 July 1975. Smoliak 
and Gschaid 3314. 

Reported as being an escape (Moss 1959). Reported by 
Boivin (1972). 

LABIATAE 

Moldavica thymiflora (L.) Rydb. 

Porcupine Hills. Waldron ranch roadside. 6 June 1969. 

Allen and Johnston 2430. 

Whaleback Ridge. Dry shale slope. 21 June 1972. 

Allen 2729. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1972). 
Nepela cataria L. 

Lethbridge. Oldman River valley. 2 August 1968. 

Allen 2311. 

Magrath. Creek area. 5 August 1976. Smoliak 3429. 

Very rare in Alberta (Moss 1959). Reported by Boivin 

(1972). 
Salvia nemorosa L. 

Monarch. River valley. 20 July 1935. No name 875. 



Claresholm. Dry roadside. 29 July 1966. Allen and 

Gschaid 2072. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1972). 

SOLANACEAE 

Solarium rostratum Dunal* 

Pincher Creek. Roadside. 24 August 1966. Kettles 2098. 
Reported by Boivin (1972) and Packer and Dumais 
(1972). 

SCROPHULARIACEAE 

Castilleja sessiliflora Pursh* 

MRS. Sandy area. 30 June 1975. Smoliak and Berg 

3213. 

MRS. Sandy area. 3 June 1976. Smoliak and Gschaid 

3399. 

Not previously reported for Alberta. 
Penstemon fruticosus (Pursh) Greene subsp. scouleri 
(Lindl.) Penn. and Keck* 

Crowsnest Pass. Rocky banks. 1 July 1932. White 674. 

Apparently rare in Alberta (Moss 1959). Reported by 

Boivin (1972). 
Penstemon montanus Greene* 

Prairie Bluff Mountain. Open pine woods. 12 July 

1966. Allen and Gschaid 2074. 

Not previously reported for Alberta. 

LOBELIACEAE 

Downwingia laeta Greene* 
Walsh. Mud and shallow water. 26 June 1969. Gschaid 
and Allen 2434. 

Rare in Alberta (Moss 1959). Reported by Boivin 
(1972). 

COMPOSITAE 

Anthemis tinctoria L. 

Waterton Lakes National Park. Waste area. 1 Septem- 
ber 1974. Bohus 3182. 

Uncommon in Alberta (Moss 1959). Reported by 

Boivin (1972). 
Aster maccallae Rydb.* 

Allison Lake. Moist shaded area. 22 August 1972. 

Gschaid and Allen 2814. 

Reported by Porsild (1959), Boivin (1972), and Packer 

and Dumais (1972). 
Aster simplex Willd.* 

Lethbridge. Oldman River valley. 4 September 1972. 

Allen 2824. 

SRS. Moist coulee. 15 September 1973. Allen 3060. 

Not previously reported for Alberta. 
Bahia oppositifolia (Nutt.) DC* 

West Lethbridge. Cultivated field. 15 July 1969. 

Sexsmith 2458. 

Found locally near Lethbridge (Moss 1959). Reported 

by Boivin (1972). 
Cenlaurea diffusa Lam. 

Crowsnest Pass. Roadside. 10 September 1973. Wil- 
liamson, Gschaid, and Allen 3065. 

Reported by Boivin (1972) and Packer and Dumais 

(1972). 
Centaurea maculosa Lam. 

Waterton Lakes National Park. Roadside. 2 Septem- 
ber 1967. Allen, Smoliak, and Gschaid 2153. 

Crowsnest Pass. Roadside. 22 August 1972. Gschaid 



1978 



Notes 



89 



and Allen 2820. 

Kipp. Roadside. 3 August 1973. Gschaid 3027. 

Not previously reported for Alberta. 
Cichorium intybus L. 

Lethbridge. Roadside. 5 August 1942. Sexsmith 1323. 

Apparently rare in Alberta (Moss 1959). Reported by 

Boivin(1972). 
Chrysanthemum leucanthemum L. 

Crowsnest Pass. No location. 1 July 1932. White 695. 

Hillcrest. Open woods. 29 June 1958. Johnston and 

Allen 1745. 

AUison Creek. Clearing. 3 October 1962. Allen 1913. 

LRS. Shaded area. 12 June 1973. Smoliak and Allen 

2893. 

Waterton Lakes National Park. Roadside. 1 September 

1974. Bohus 3183. 

Reported for few localities (Moss 1959). Reported by 

Boivin(1972). 
Hieracium aurantiacum L. 

Cardston. Lawn. 20 June 1972. Steed 2739. 

Rare in Alberta (Moss 1959). Reported by Boivin 

(1972). 
Senecio foetidus Howell* 

Beauvais Lake. Moist woods. 1 July 1964. Sexsmith 

1959. 

Pincher Creek. Moist meadow. 11 July 1972. Gschaid 

and Allen 2789. 

Reported by Boivin (1972) and Packer and Dumais 

(1972). 
Silybum marianum (L.) Gaertn. 

Coaldale. Cultivated area. 12 September 1973. Allen 

3064. 

LRS. Greenhouse. 4 April 1975. Bohus 3187. 

Reported by Boivin (1972). 
Sonchus oleraceus L. 

Lethbridge. Garden. 2 August 1970. Allen 2578. 

Not common in Alberta (Moss 1959). Reported by 

Boivin (1972). 
Townsendia hookeri Beaman* 

Lethbridge. Coulee slope. 23 April 1969. Smoliak and 



Allen 2340. 

SRS. Gravelly ridge. 20 May 1970. Allen 2488. 

Reported by Beaman (1957). 

Literature Cited 

Beaman, J. H. 1957. The systematics and evaluation of 
Townsendii (Compositae). Contributions from the Gray 
Herbarium of Harvard University 183: 1-151. 

Boivin, B. 1967. Flora of the Prairie Provinces. Part 1. 
Provancheria 2: 1-202. 

Boivin, B. 1969. Flora of the Prairie Provinces. Part 2. 
Provancheria 3: 1-185. 

Boivin, B. 1972. Flora of the Prairie Provinces. Part 3. 
Provancheria 4: 1-224. 

Frankton, C. and L J. Bassett. 1968. The genus Atriplex 
(Chenopodiaceae) in Canada. L Three introduced species: 
A. heterosperma, A. oblongifolia, and A. hortensis. Cana- 
dian Journal of Botany 46: 1309-1313. 

Frankton, C. and I.J. Bassett. 1970. The genus Atriplex 
(Chenopodiaceae) in Canada. IL Four native western 
annuals: A. argentea, A. truncate, A. Powellii, and A. 
dioica. Canadian Journal of Botany 48: 981-989. 

Hitchcock, C. L. and A. Conquist. 1973. Flora of the 
Pacific Northwest. An illustrated manual. University of 
Washington Press, Seattle and London. 730 pp. 

Johnson, H. and B. Hallworth. 1975. Further discoveries 
of sand verbena in Alberta. Blue Jay 33: 13-15. 

Moss, E. H. 1959. Flora of Alberta. University of Toronto 
Press, Toronto. 546 pp. 

Packer, J. G. and M. G. Dumais. 1972. Additions to the 
flora of Alberta. Canadian Field-Naturalist 86: 269-274. 

Porsild, A. E. 1959. Botanical excursion to Jasper and 
Banff National Parks, Alberta: alpine and subalpine 
flora. National Museum of Canada. 38 pp. 

Rydberg, P. A. 1932. Flora qf the Prairies and Plains of 
central North America. New York Botanical Garden. 
969 pp. 

Received 8 March 1977 
Accepted 2 October 1977 



European Flounder {Platichthys flesus) Captured in 
Lake Erie, Ontario 



A. R. Emery' and G. Teleki^ 

'Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6 

^British Columbia Hydro and Power Authority, 118 Bernard Nelson Crescent, Revelstoke, British Columbia VOE 2S0 

Emery, A. R. and G. Teleki. 1978. European Flounder {Platichthys flesus) captured in Lake Erie, Ontario. Canadian 
Field-Naturalist 92(1): 89-91. 

Two specimens of Platichthys flesus, the flounder, from Europe, were captured alive in different localities in Lake Erie, far 
from the fish's normal oceanic or estuarine habitat. Evidence from stomach contents suggested some residence time in the lake 
and immigration is speculated to have been via a ship's ballast tank. 

Key Words: flounder, Platichthys flesus. Lake Erie, exotic species, zoogeography, introduction. 



90 



The Canadian Field-Naturalist 



Vol. 92 



The Flounder, Platichthys flesus, normally occurs 
in European waters of the Atlantic north to the White 
Sea, but is also known from the Adriatic and Black 
Seas. It is particularly common in the Baltic Sea, and 
also the southern and eastern coastal North Sea 
(Wheeler 1969). This flounder is well known as the 
only European flatfish to penetrate well into estuaries 
and to live in fresh water for periods of time. It is 
common in water shallower than 55 m, and makes 
extensive migrations (30 to 60 km), although many 
marked flounders have been observed not to migrate 
significantly. Entries into fresh water are noted mainly 
in the summer but no spawning has been observed 
there. 

The first specimen captured in Lake Erie was taken 
by a bait seine off Nigger Road, on Long Point, 
Ontario, some 1200 to 1500 km from the nearest 
brackish-water incursion into the Gulf of St. Law- 
rence and almost a quarter of the way around the 
world from its normal range. 

The specimen (Figure 1) was captured alive on 3 
July 1974 at 1000 hours in 1 m of water along a sand 
and gravel beach. It was measured and photo- 
graphed prior to preservation (Royal Ontario 
Museum No. 30521). 

The fish was 187.7 mm total length (158.3 mm 
standard length) and an examination of 10 scales 
suggested an age of 2 years. This showed about the 
average growth rate recorded by Wheeler (1969) for 
European waters. Two of the scales were regenerated, 
a not unusual proportion. 



Stomach contents were examined, and although 
preservation was poor, because of the digestion that 
had taken place, R. McKay (University of Toronto) 
confirmed that the chironomids that made up part of 
the stomach contents were typical freshwater forms. 
Specific identification was not possible. Small clam 
shells, also present in the contents, were examined by 
D. G. Cook (formerly at Canada Centre for Inland 
Waters); he confirmed that these were in the genus 
Pisidium. Pisidium spp. are abundant small bivalve 
clams in the Great Lakes and possess unique features 
that make it difficult to confuse with marine or 
brackish-water forms. 

The second specimen was captured a year and a half 
later on 3 January 1976, by Robert Foote of Port 
Burwell, Ontario. It was taken with trawling gear at a 
depth of "120 to 130 ft of water" (37 to 40 m), about 
2 mi (3.2 km) south of Port Dover on Lake Erie. It 
was kept alive by Mr. Foote for approximately 5 h 
after capture. This specimen was considerably larger 
(347 mm total length) and had been gutted before 
being iced and brought to our attention. 

This species is normally dextral. The first and 
smaller specimen was dextral, but the second and 
larger specimen was sinistral. In both cases, the 
specimens were in excellent condition with no 
evidence of broken fins or damaged scalation. 

We wondered whether the specimens might be the 
result of a hoax, and have gone to some effort to 
establish the veracity of the records. We are now 
convinced of the integrity of the collectors. Their 




Figure I. A European Flounder, Plalichihvs flesus {ROM 30521), 187.7 m total length, taken from Lake Erie, Ontario on 
3 July 1974. 



1978 



Notes 



91 



claim that the fish had been taken in fresh water was 
confirmed, at least in the case of the smaller specimen, 
by the presence of typical freshwater organisms of 
types a fisherman would not "feed" a fish {Pisidium 
clams and chironomid larvae). 

Although we are skeptical of any spectacular 
anomaly in the geographic range of an animal. Lake 
Erie has already seen the arrival and establishment of 
some species of marine fish. Unlike the flounder, 
however, these species (e.g.. Rainbow Smelt, Osmerus 
mordax; Sea Lamprey, Petromyzon marinus; and 
Ale wife, Alosa pseudoharengus) are anadromousand 
have landlocked examples in other areas and a history 
of occurrence in Lake Ontario. More recently, a large 
exotic crab, the Mitten Crab {Eriocheir sinensis) 
originally from northern China and first reported in 
Lake Erie in 1973 (Nepszy and Leach 1973) has, 
apparently, managed to reach the lake in numbers. 
Nepszy and Leach do not believe that it has 
established a reproductive population. This latter is 
an analogous situation to the European Flounder 
being found in Lake Erie. 

The mode of arrival of the flounder and of the 
Mitten Crab may be similar: the ballast tanks of 
ocean-going vessels. We have no real proof in either 
case. A comparison of the Mitten Crab and the 
flounder as equally aggressive invaders of Lake Erie 
is appropriate; the Mitten Crab is extensively 
distributed in areas of Europe now (Hoestlandt 1959; 
Kaestner 1970). There is ample evidence of the 
flounder migrating into European fresh water. The 
speculation that the flounder may have access to 



Lake Erie regularly in the future, and the evidence 
provided by stomach contents that it can feed in fresh 
water suggests that it will be captured irregularly in 
the future. Because it moves into fresh water in 
Europe but cannot reproduce, indicates that there 
is little likelihood of a population of Plat ichthys fie sus 
becoming established in Lake Erie. 

Acknowledgments 

We are grateful to the collectors Louis Kociuk and 
Ronald Biddle of Port Rowan for bringing the first 
specimen to our attention and to Robert Foote of Port 
Burwell for the second specimen. We thank W. B. 
Scott and E. J. Crossman for critical comments on the 
manuscript. Thanks are also extended to D. G. Cook 
and R. McKay for assistance with the identification of 
stomach contents. 

Literature Cited 

Hoestlandt, H. 1959. Repartition actuelle du crabechinois. 

Bulletin frangais de Pisciculture 194: 1-13. 
Kaestner, A. 1970. Invertebrate zoology. III. Crustacea. 

John Wiley and Sons, Inc., New York. 523 pp. 
Nepszy, S.J. and J.H. Leach. 1973. First records of the 

Chinese mitten crab. Eriocheir sinensis (Crustacea: Brach- 

yura) from North America. Journal of the Fisheries 

Research Board of Canada 30: 1909-1910. 
Wheeler, A. 1969. The fishes of the British Isles and 

northwest Europe. Michigan State University Press, 

East Lansing, Michigan. 613 pp. 

Received 4 October 1977 
Accepted 4 November 1977 



Site and Seasonal Variations in Food of Wolves, 
Algonquin Park, Ontario 

John B. Theberge,' Sebastian M. Gosenbrug,' and Douglas H. Pimlott^ 

'Department of Biology, University of Waterloo, Ontario N2L 3G1 
^Department of Zoology, University of Toronto, Toronto, Ontario M5S lAl 

Theberge, John B., Sebastian M. Oosenbrug, and Douglas H.Pimlott. 1978. Site and seasonal variations in food of wolves, 
Algonquin Park, Ontario. Canadian Field-Naturalist 92(1): 91-94. 

Wolf ( Canis lupus) scats collected in Algonquin Provincial Park during the summer in 1 97 1 and 1 974 demonstrated that food 
items in scats at rendezvous sites differed from those in scats elsewhere. Beaver (Castor canadensis) was more common in the 
former. Since all five rendezvous sites were adjacent to active beaver colonies, it is apparent that local food resources were 
being exploited. White-tailed Deer (Odocoileus virginianus) was more common away from rendezvous sites. Winter scats 
differed from those of summer by having a greater percentage of deer hair and less of beaver. 

Key Words: wolf, Algonquin Park, predation. 



The food of wolves has changed markedly over the 
past decade in Algonquin Park, concurrent with a 



decline in deer and increase in beaver numbers (Voigt 
et al. 1976). 



92 



The Canadian Field-Naturalist 



Vol. 92 



In summer wolf (Canis lupus) scats the frequency of 
occurrence of hair from White-tailed Deer {Odo- 
coileus virginianus) dropped from 80.5% in the years 
1959 to 1965 (Pimlott et al. 1969), to 33% in 1972 
(Voigt et al. 1976), while that of Beaver {Castor 
canadensis) increased from 7.1% to 55%. 

We collected 220 wolf scats in the summers of 1971 
and 1974 from the central and southern parts of 
Algonquin Park, in the same but slightly larger area 
from which the collections of Pimlott et al. (1969) and 
Voigt et al. (1976) were made. Unlike these other 
collections, however, we subdivided our collection 
into winter and summer scats, and into summer scats 
collected at wolf rendezvous sites versus those 
collected away from rendezvous sites. Differences in 
these categories further elucidate the changes occur- 
ring in wolf-prey dynamics in Algonquin Park. 

Study Area 

Data were collected from approximately 1700 km^ 
of central and southern Algonquin Park. Algonquin 
Park is situated near the southern edge of the 
Canadian Shield, with intrusive volcanic and meta- 
morphic rocks forming rolling hills of elevation 
varying between 152 and 518 m. Forests exhibit an 
ecotonal position between Boreal and Great Lakes- 
St. Lawrence Regions (Rowe 1959). A more complete 
description of this area is given by Pimlott et al. 
(1969). 

Methods 

Throughout the study area, 220 scats were collected 
over the periods of May to September 1971 and 1974. 
Most scats (141) were found in general searches of the 
extensive network of logging roads and portage trails; 
an additional 79 were found at wolves' rendezvous 
sites, where packs commonly spend a week or more at 
a time throughout the summers (Joslin 1967). 
Rendezvous sites were located by giving vocal 
imitations of wolf howls to which wolves responded, 
taking bearings, and after the wolves left, by 
examining the area (D. H. Pimlott, 1960. The use of 
tape-recorded wolf howls to locate timber wolves. 
Twenty-second Midwest Fish and Wildlife Con- 
ference, Toronto. 7 pp. mimeo). 



Scats were classified as winter (period of snow on 
ground; ungulates in winter pelage) or summer based 
on when scats were collected and how fresh they 
appeared. Winter scats were leached of all organic 
matter except hair and bones, were deposited without 
new green growth beneath them, and were found on 
the first passages of various routes. Scats classed as 
unknown age were not included in the analyses. Pup 
scats within the size range, which could be mis- 
identified as those of Red Fox (Vulpes vulpes), were 
not collected except at rendezvous sites. No Coyotes 
{Canis latrans) have been reported in Algonquin Park 
to allow misidentification of scats. 

Analysis of scats was done on the basis of the 
pattern and structure of cuticular scales of hair, as 
described by Williamson (1951). After being washed 
through a sieve, hairs in scats were spread out in petri 
dishes, and representative hairs were checked by 
making impressions in commercial gelva (polyvinyl 
acetate) and by examining them microscopically. A 
collection of hairs at the University of Waterloo from 
known species of wildlife, and the guide to cuticular 
hair scales (Adorjan and Kolenosky 1969) were used 
to identify the hairs in scats. The hairs of White-tailed 
Deer and Moose {Alces alces) were distinguished as 
from summer or winter, but we were unable to 
separate consistently and positively the hairs of 
young-of-the-year from adults for these two species. 

For each scat, all species identified as food items 
were listed. Analysis was done on percent frequency of 
occurrence of food items to be consistent with 
analyses of earlier data. Scats collected in 1971 (124) 
and 1974 (96) were combined. Preliminary analyses by 
year showed no differences other than that at- 
tributable to smaller sample sizes. 

Results 

The 163 summer scats showed the following percent 
frequency of occurrence of hair: beaver, 49.0; deer, 
28.9; moose, 14.7; and other, 7.3. 

Significant differences were apparent when these 
scats were subdivided into those collected at wolf 
rendezvous sites and those collected in general 
searches elsewhere (Table 1). Beaver represented 
62.8% of food items in scats at rendezvous sites (out of 



Table 1 — Percent frequency of food items in summer wolf scats collected in wolf rendezvous sites and in general 

searches, Algonquin Park, 1971 and 1974 



Location 


Total 














Total 


of scats 


scats 


Beaver 


Deer 


Moose 


Hare 


Microtines 


Other 


items 


Rendezvous 


















sites 


79 


62.8 


20.5 


9.8 


1.0 


3.0 


3.0 


102 


General 


















search 


84 


35.3 


37.3 


19.5 


2.0 


3.0 


3.0 


102 



1978 



Notes 



93 



a total of 102 food items), but only 35.3% in scats from 
elsewhere. Under-represented in scats collected at 
rendezvous sites was deer, which made up 20.5% of 
food items at rendezvous sites compared with 37.3% 
in general searches, and moose making up 9.8% and 
19.5% respectively. 

Food items that occurred infrequently in summer 
scats included Snowshoe Hare (Lepus americanus), 
1 .5%; small rodents either Microtus pennsylvanicus, 
Peromyscus sp., or Synaptomys cooperi, 2.4%; or 
Black Bear {Ursus americanus), 1.5%; and single 
occurrences of Eastern Chipmunk {Tamias striatus), 
Northern Flying Squirrel {Glaucomys sabrinus), 
raccoon (Procyon lotor), and fish scales. Four more 
occurrences of Black Bear hairs were found in scats 
collected at one rendezvous site, but these were not 
included because of the proximity of a dump where 
the Ontario Ministry of Natural Resources disposed 
of bears they killed. 

Winter scats showed marked differences from 
summer scats. Our total of 78 food items in 57 scats 
showed the following percent frequencies of occur- 
rence of hair: deer 64.0, moose 16.7, beaver 11.5, 
microtines 2.6, and other (Raccoon, bear, and Red 
Squirrel {Tamiasciurus hudsonicus)) 5.1. The first 
three species, when combined, contributed approxi- 
mately the same amounts in summer (92.6%) as in 
winter (92.2%), but beaver hair was much less 
common in winter, and that of deer was more 
common. 

Discussion 

The food items in the summer scats were similar to 
those described by Voigt et al. (1976) for 1972, which 
showed occurrences for beaver and deer at 55% and 
33% respectively. We found a greater occurrence of 
moose (14.7%) than did Voigt in 1972 (5%), but a 
similar percent to his 1969 figure (15%). 

The differences in food items in summer scats 
collected at rendezvous sites compared with those 
collected elsewhere reflects general rather than 
absolute differences in what wolves eat in these places, 
because wolves may travel some distance after eating 
before they defecate. Some members of the pack, 
however, are more sedentary than others, such as a 
mother of pups (Murie 1944), and such animals Ukely 
contributed more to the collection at rendezvous sites. 
The difference in food items at, versus away from, 
rendezvous sites suggests that general collections of 
scats made to determine food habits should include 
scats found at rendezvous sites. We consider that our 
total summer collection provided as close to an 
accurate estimate of summer food habits as possible 
on the basis of equal representation of food items 
collected in both places (102 items each), and close to 
equal numbers of scats (79 and 84). Although no exact 



estimate can be made of the relative amounts of time 
that most members of the pack spend at or away from 
rendezvous sites, our best estimate is close to 50:50. 
Based on continuous observations at sites, Theberge 
and Pimlott (1969) observed that normally wolves 
spend most of the daylight hours at rendezvous sites 
and that at night most of the adults are away. All five 
rendezvous sites where we collected scats were within 
0.5 km of active beaver colonies, as is often typical of 
such sites (Joslin 1967); hence, the higher proportion 
of beaver hair in scats collected there. Our results, 
demonstrating utiHzation by wolves of non-ungulate 
prey resources near rendezvous sites, contrasts with 
Peterson's (1974) conclusion that wolves on Isle 
Royale, Michigan, did not hunt beaver close to 
rendezvous sites. 

Wolf scats representing the winter period, while 
small in sample size, show a marked difference from 
the 50 winter scats reported for 1962 by Pimlott et al. 
(1969). Deer hair dropped from 90% in 1962 to 64% in 
1971-1974; moose and beaver hair combined in- 
creased from 10% to 27.2%. Although both samples 
are too small for detailed comparison, these results are 
consistent with those of Pimlott et al. (1969) who 
found deer hair more common in winter scats than in 
summer scats. 

Acknowledgments 

We thank graduate student David Gauthier, and 
undergraduate students Andrew Gordon and Owen 
Williams for their field assistance. Dan Strickland, 
Ministry of Natural Resources, and his naturalist staff 
provided many helpful observations. The study was 
funded in 1971 by a grant from the Elsa Wild Animal 
Appeal of Canada. The Ministry of Natural Re- 
sources sanctioned the study and gave us permission 
to use closed logging roads, which was essential to 
adequate coverage of the study area. 

Literature Cited 

Adorjan, A. S. and G. B. Kolenosky. 1969. A manual for 

the identification of hair of Ontario mammals. Ontario 

Department of Lands and Forests Research Report 

(Wildlife). 64 pp. 
Joslin, P. W. B. 1967. Movements and home sites of timber 

wolves in Algonquin Park. American Zoologist 7: 279- 

288; 
Murie, A. 1944. The wolves of Mt. McKinley. U.S. 

National Park Service, Fauna Series 5. 238 pp. 
Peterson, R. O. 1974. Wolf ecology and prey relationships 

on Isle Royale. Ph.D. thesis, Purdue University, La- 

feyette, Indiana. 368 pp. 
Pimlott, D. H., J. A. Shannon, and G. B. Kolenosky. 

1969. The ecology of the timber wolf in Algonquin 

Provincial Park. Ontario Department of Lands and 

Forests Research Report (Wildlife) Number 87. 92 pp. 
Rowe, J. S. 1959. Forest regions of Canada. Canadian 

Department of Northern Affairs and National Resources, 



94 



The Canadian Field-Naturalist 



Vol. 92 



Bulletin 123. 71 pp. 
Theberge, J. B. and D. H. Pimlott. 1969. Observations of 

wolves at a rendezvous site in Algonquin Park. 

Canadian Field-Naturalist 83(2): 122-128. 
Voigt, D. R., G. R. Kolenosky, and D. H. Pimlott. 1976. 

Changes in summer foods of wolves in central Ontario. 



Journal of Wildlife Management 40(4): 663-668. 
Williamson, V. H. H. 1951. Determination of hairs by 
impressions. Journal of Mammalogy 32: 80-84. 

Received 21 April 1977 
Accepted 28 September 1977 



Durability of Tree Holes Used by Buffleheads 



Anthony J. Erskine 

Canadian Wildlife Service, Sackville, New Brunswick EOA 3C0 

Erskine, A. J. 1978. Durability of tree holes used by Buffleheads. Canadian Field-Naturalist 92(1): 94-95. 



Nesting studies of Buffleheads {Bucephala albeold) 
in the Cariboo parklands of British Columbia in 
1 957-1 965 gave some data on permanence of nest sites 
(Erskine, A. J. 1972. Buffleheads. Canadian Wild- 
life Service, Monograph Series Number 4, Table 9). 
That period of study was too short to cover the 
potential durability of tree-hole nests. Accordingly, I 
revisited as many as possible of the former nest sites 
on 10-13 July 1975. This was after the nesting season, 
and only one site had clearly been used and two more 



possibly used in 1975. But more sites were still 
standing and apparently usable than had been 
predicted earlier: "About half of the known sites in 
aspens were no longer available six years after they 
were first found, and probably few last more than ten 
years... Over 80 per cent of nests in Douglas firs were 
still available four years later..." (Erskine, op. cit., 
p. 69). Samples were then too small to extrapolate 
further. 

The new data permit extension of the table, as 



Table 1 — Percentage of Bufflehead nests usable when revisited in subsequent years, British Columbia, 1957-1975 





Nests in 


aspens 








Nests in Dou 


glas firs 




Years after nest 


No. 


of nests 


_ Percent still 
usable 


Years after 
first four 


nest 
d 


No. 


of 


nests 


Percent still 


first found 


visited 


usable 


visited 




usable 


usable 


1 


81 


78 


96 


1 




40 




38 


95 


2 


76 


70 


89 


2 




36 




33 


87 


3 


70 


61 


77 


3 




32 




31 


84 


4 


60 


52 


67 


4 




27 




27 


84 


5 


49 


45 


61 


5 




24 




24 


84 


6 


43 


39 


56 


6 




24 




22 


77 


7 


38 


34 


50 


7 




22 




21 


74 


— 


— 


— 


— 


8 




20 




20 


74 



34 



31 



46 



10 



20 



19 



70 



13 


31 


30 


44 


13 


19 


18 


66 


14 


30 


27 


40 


14 


18 


17 


63 


15 


24 


22 


36 


15 


17 


15 


56 


16 


18 


11 


22 


16 


15 


13 


48 


17 


11 


8 


16 


17 


10 


9 


43 


18 
19 


3 


2 




18 


3 


1 




20 
21 


— 


= 


= 


21 


1 


1 





♦Accumulated percent thus: 78/81 x 100 = 96; 78/81 x 70/76 x 100 = 89; etc. 



1978 



Notes 



95 



follows: after 7 years, about one-half of all nests in 
trembling aspen {Populus tremuloides) and three- 
quarters of those in Douglas fir {Pseudotsuga 
menziesii) were still usable, whereas after 15 years 
about one-third of aspen nests and one-half of 
Douglas fir nests were usable. Compared to the earlier 
summary, the figures are similar up to 7 years 
(Table 1), but some nests were much more durable 
than had been thought. Possibly some trees were 
weakened by having been cut open or climbed during 
the intensive studies, and thus tended to fall soon 
afterwards, suggesting that sites were less durable 



than they actually were. Nevertheless, aspens are not 
long-lived trees, and the Douglas firs that contained 
nest holes were mostly already dead or broken off, so 
these data may be representative. Only four previous- 
ly known trees with nest holes that were no longer 
present in 1975 had evidently been felled or cleared 
away deliberately (during cottage or resort develop- 
ment); the rest were judged to have fallen from more 
natural causes. 

Received 16 September 1977 
Accepted 30 October 1977 



Range Extensions to the Flora of the Eastern Canadian Arctic 



J. R. JOTCHAM and S. P. Vander Kloet 



E. C. Smith Herbarium, Acadia University, Wolfville, Nova Scotia, BOP 1X0 



Jotcham, J. R. and S. P. Vander Kloet. 
Field-Naturalist 92(1): 95-96. 

The annual sovereignty mission by Maritime Com- 
mand into the Arctic has afforded the staff and 
students of the E. C. Smith Herbarium an un- 
paralleled opportunity to explore botanically un- 
known areas in the eastern Canadian Arctic. Although 
most of our interest has focussed on clarifying 
biosytematics of the polymorphic Vaccinium uligi- 
nosum, we have nevertheless accumulated distri- 
butional data of species associated with that species, 
some of which represent significant range extensions. 
Occasionally we visited a site where V. uliginosum was 
absent, in which case a general collection was made. A 
total of 146 species of vascular plants was collected 
over a 4-year period, 1972-1975. Specimen vouchers 
have been deposited in ACAD.* 

Collections from some sites, such as Coburg Island 
(75°49'N, 79°27'W), Makinson Inlet (three sites: 
77°19'N, 82°14'W: 77°16.5'N, 81°13'W: and 77° 
10.5'N, 81°35'W) are the first for these locations. 
No major extensions were noted at these sites. The 
specimens collected from Coburg Island were Salix 
arctica, Cerastium alpinum, Draba bellii, and 
Cassiope tetragona. Plants from the Makinson Inlet 
sites were Carex rupestris, Carex misandra, Salix 
arctica, Polygonum viviparum, Papaver radicatum, 
Cochlearia officinalis, Draba bellii, Braya purpura- 
sens, Saxifraga cernua, Saxifraga oppositifolia, Dryas 
integrifolia, Cassiope tetragona, and Pedicularis 
lanata. 

*Acronyms follow Index Herbariorum, Holmgren & 
Keuken (1974). 



1978. Range extensions to the flora of the eastern Canadian Arctic. Canadian 



In addition, some species were collected from areas 
for which there seems to be no previous record, and 
range extensions are indicated for at least three 
species. These extensions are based primarily on 
distribution maps in Porsild( 1964) and Hulten(1968), 
and from annotations on specimens deposited at CAN 
and DAO. 

Poa alpigena var. colpodea — Occasional in wet gravel by 
river (Strathcona Sound, 73°07'N, 84°25'W: 1975. 

This collection is on the eastern fringe of the known range 
for the Canadian Arctic. The variety also occurs in northern 
Greenland (Porsild 1964). 

Dupontia fisheri ssp. psilosantha — Common in mesic 
gravel by river (Strathcona Sound, 1975). 

This collection would be on the northern fringe of the 
range as indicated by distribution maps. CAN, however, has 
one collection from Expedition Fjord, Axel Heiberg Island 
(Beschel, CAN #293413). Our collection helps fill in the 
known distribution for this subspecies. 

Juncus arcticus — Common in wet sand by river (Strathcona 
Sound. 1975). 

Distribution maps for this species indicate a northern limit 
about 300 km farther south, near River Clyde on Baffin 
Island (Porsild 1964). CAN has one collection from 
Tanquary Fjord, Ellesmere Island, considerably to the north 
(G. R. Brassard, CAN #296268). Our collection helps to fill 
in this distributional gap. 

Luzula spicata — Associated with Vaccinium uliginosum on 

exposed granitic soil (Pond Inlet, 72°38'N, 77°50"W; 1973). 

This collection is a range extension of over 400 km to the 

north from previous collection sites at Cumberland Sound, 



96 



The Canadian Field-Naturalist 



Vol. 92 



Baffin Island (Porsild 1964). This species is found at similar 
latitudes in Greenland (Porsild 1964). 

Braya humilis ssp. arctica — Rare, on exposed gravel slopes 
(Strathcona Sound, 1975). 

This collection is an extension to the south-east of the 
known range. Porsild (1964) shows collection points on Axel 
Heiberg Island and on Victoria Island. In addition, CAN has 
one collection from Irene Bay, Ellesmere Island, 72°02'N, 
81°50'W (Irene Waterson #106/72). 

Arctostaphylos rubra — Common on exposed rocky slopes 
(Strathcona Sound, 1975). 

This collection is a range extension of over 400 km to 
the north. Porsild (1964) shows a collection site on West 
Baffin Island, just east of Prince Charles Island. 

A complete species list of the plants collected is 
available and may be obtained by contacting the 
authors. It will be updated regularly with data from 
ongoing and future expeditions by Acadia University 
in conjunction with Maritime Command. 

Acknowledgments 

We express our great appreciation to the Depart- 
ment of National Defence, Maritime Command, for 



giving us the opportunity to explore the Canadian 
Arctic and providing logistical support. We also 
thank W. J. Cody of Agriculture Canada and J. M. 
Gillett of the National Museum of Natural Sciences 
for courtesies extended during the research in Ottawa. 
Thanks are due to G. W. Argus of the National 
Museum of Natural Sciences, M. Barkworth and 
G. A. Mulligan of Agriculture Canada for aid in 
identifying specimens. In addition, we are indebted to 
W. J. Cody for critically reading the manuscript and 
providing helpful suggestions. 

Literature Cited 

Holmgren, P. K. and W. Keuken. 1974. Index Herb- 
ariorum. Part I. The herbaria of the world. 6th edition. 
Oosthoek, Scheltema, S. Holkema, Utrecht, Netherlands. 

Hulten, E. 1968. Flora of Alaska and neighboring terri- 
tories. Stanford University Press, Stanford, California. 
1008 pp. 

Porsild, A. E. 1964. Illustrated flora of the Canadian Arctic 
Archipelago. 2nd edition, revised. National Museum of 
Canada Bulletin 146: 1-218. 

Received 14 June 1977 
Accepted 3 October 1977 



News and Comment 



Notice of change to the By-Laws of The Ottawa Field-Naturalists' Club 

A motion to change By-Law 2 of The Ottawa Field-Naturalists' Club was passed unanimously by the Council 
at the meeting of 3 October 1977. 

This By-Law now reads as follows: 
2. Fiscal Year 

The fiscal year of the Club shall start at the beginningof October of any given year and shall end at the end of 

September of the following year. 

Diana R. Laubitz, 
Recording Secretary 



Earthwatch — Offers Field Research to the Public 



Earthwatch is a non-profit organization which 
offers people the chance to share the adventure and 
discoveries of field research. Earthwatch expeditions 
are open to anyone 16 to 75 and no special skills are 
required as participants are taught what they need to 
know in the field. Participants become working 
members of an expedition team and work under the 
supervision of a professional research scientist. They 
are required to make tax-deductible contributions of 
the order of $500 to $950 (usually for 2- or 3-week 
periods) to subsidize the research effort. 

Since it began in 1971, Earthwatch has had nearly 
2600 volunteers join research teams in support of over 
300 scientists conducting research in 45 countries. 
Field research expeditions cover many disciplines, 
e.g., archaeology, anthropology, humanities, and 
earth, marine, and life sciences. In early 1978 
volunteers will join expeditions to observe the 
behavior of the guanaco in the Andean foothills of 
southern Chile; record songs of the humpback whale; 



study tropical forest ecology; excavate a Mayan site in 
coastal Guatemala; study the coral reef ecosystem off 
Grenada; monitor raccoon movements by radio- 
telemetry; observe predator behavior towards small 
fish with different color patterns; study the response 
of gulls and terns to the declining water levels of the 
Great Lakes; etc. 

All of the projects submitted to Earthwatch for 
support are first reviewed and approved by The 
Center of Field Research, wjiich has an impressive list 
of scientists on its Board of Advisors. All of the 
programs are designed to improve the public's access 
to scientists, to foster private sponsorship of research, 
and to inspire interested citizens to get involved. 

If you are interested in a working experience (not a 
guided tour or educational field trip) to share the life 
of professionals seeking solutions to real problems 
then contact Earthwatch, Box 127 A, Belmont, 
Massachusetts 02178 or call (617) 489-3030. 



ASC Information Center 



The Association of Systematics Collections (ASC) 
was founded in 1972 in part to meet the need for a 
single information center to organize and offer 
information regarding the wealth of available natural 
history taxonomic resources and services. 

Operation of the ASC Information Center was 
initiated on September 1, 1977. At present, the Center 
can provide the names and addresses of systematists 
and systematics collections, as identified by speciality. 
This information is supplied through the Registry of 
Taxonomic Resources and Services — a data base 
developed by the ASC with the support of the USA 
Energy Research and Development Administration. 
The Center provides two levels of service. The 



Fundamental List is a complete listing of those 
persons or collections that satisfy the stipulations of 
the inquirer. In the Total Plan, ASC personnel 
contact each individual identified by the Fundamental 
List to determine their willingness to participate in a 
project or problem outlined by an inquirer. 

Initially all inquiries will be handled free of charge. 
Inquiries or requests for more information should be 
directed to Rebecca Pyles, ASC Secretariat Office, 
Museum of Natural History, The University of 
Kansas, Lawrence, Kansas 66045 or by phone at (9 13) 
864-4867. It is hoped the Center will provide access to 
the biologists who represent a much needed resource 
to both science and society. 



97 



98 



The Canadian Field-Naturalist 



Vol. 92 



Request for Information about Leaf-Fall Dates 1950 to 1976 



The Ontario Ministry of Natural Resources is 
involved in a long-term study of White-tailed Deer in 
northern Frontenac County. Part of this study 
concerns the effects of autumn weather, including 
leaf-fall. 

In order to supplement existing records, any 
information regarding leaf-fall dates (80% of de- 
ciduous leaves fallen) for eastern Ontario would be 



greatly appreciated. For each year please give date(s), 
location(s), and other observations such as principal 
tree species, and whether leaf-fall had been relatively 
sudden or gradual. 

Please contact Peter Smith, Ontario Ministry of 
Natural Resources, Fish and Wildlife Research 
Branch, P.O. Box 50, Maple, Ontario LOJ lEO. 



Museum Collections and Canadian Science 

From a brief submitted to the Secretary of State of Canada by the Biological Council of Canada 



A cardinal tenet of scientific methodology is that 
reported findings should be subject to later review. In 
all taxonomic work and in studies such as ecological 
surveys which depend on the correct identification of 
the biological organisms examined, it is imperative 
that the material on which the work was based is 
maintained for future validification. Because of the 
incredible diversity of living forms, this essential re- 
assessment of previous work and continued orderly 
progress in the growth of knowledge is possible only 
by the use of an international hierarchical system of 
classification. Communication about the taxonomic 
groups thus recognized is possible only by adherence 
to a strict system of nomenclature. Moreover, this 
system of nomenclature is the key to the data retrieval 
system enabling results from all types of experiments, 
observational, analytical, and applied research, to be 
correlated and compared. 

For well over 100 years the desirable practice of 
designating and preserving voucher specimens result- 
ing from any form of biological research has become 
common as a documented record of precise taxa to 
which the data from a particular study pertain. 

More recently the designation and preservation of 
holotype specimens has also been recognized as of 
central importance in making the nomenclatural 
classification effective. 

To be of value to science, these type and voucher 
specimens must be preserved indefinitely as perma- 
nent reference materials. They are a sacred trust from 
the 20th century science to future generations. Many 
intensive and expensive research studies of the past 
have had their results rendered of questionable value 
when serious doubt arises about the precise taxa 
involved. In the absence of voucher specimens, the 
entire research would have to be duplicated to resolve 
the validity of published results. Of equal importance, 
from the point of view of preservation, are large 
research collections of specimens serving as data-rich 
"samples" of contemporary populations of living 
organisms. 



The National Botanical and Zoological Collections 
are presently receiving inadequate financial support, 
so that some taxonomic groups are completely 
ignored while others are only minimally served.* 

This neglected state of our National Collections is 
of considerable concern to the Biological Council of 
Canada, but the situation for other biological 
collections, presently housed across Canada in 
provincial or municipal departments and museums, 
universities, colleges, etc., is already critical. These 
regional collections receive, for the most part, little 
federal financial support and have to depend on a 
variety of other sources for funding. They maintain 
valuable and representative specimens of the regional 
fauna and flora of Canada, however, and in some 
cases have specialized Canadian collections that are as 
good or better than the designated National Collec- 
tions. Regional Collections are, therefore, just as 
much as part of our national heritage as are the 
National Collections themselves, and are also an 
essential natural resource serving the interests of the 
public and the research and study needs of universities 
and provincial departments of Agriculture, Forestry, 
Fisheries and Wildlife, etc., as well as being important 
for epidemiological and ecological studies. 

*It is appropriate that the National Museum of Natural 
Sciences should have primary responsibility for curating 
type material. This Museum currently has national 
responsibility for most animal groups both recent and 
fossil and for all living botanical taxa (except fungi) and 
some fossil plant groups. 

Agriculture Canada also houses the National Collections 
of fungi, insects, arachnids, mites, as well as a very large 
botanical herbarium. These, like the National Museum of 
Natural Sciences, are maintained with scientific curatorial 
staff of international repute, but of dwindling numbers as 
vacant positions are not refilled. 

Other major Canadian collections include bacteria 
(National Research Council); freshwater algae (Canada 
Centre for Inland Waters); and the National Collection of 
invertebrate fossils and some plant fossils (Geological 
Survey of Canada). 



1978 



News and Comment 



99 



Because of the scattered nature of these regional 
collections and the fact that there is no national 
register of what is being held in such collections, it is 
presently impossible to make sound recommenda- 
tions on the steps that must be taken to protect and 
preserve, for the future, this important part of our 
national heritage. 

The Biological Council of Canada therefore urges 
that the Secretary of State of Canada establish a 
Commission of Enquiry with the following objectives: 



1. A careful survey and documentation of existing 
biological collections in Canada, including culture 
and germplasm depositories; 

2. An assessment of their regional, national, and 
international value as collections; 

3. Recommendations for regional resource centers 
worthy of federal support and specific proposals 
to ensure the financial stability of such centers in 
order that they may fulfill their dual function of 
serving society and science throughout Canada. 



Wanted — Sightings of Sandhill Cranes in Northern Ontario 



The Greater Sandhill Crane breeds throughout the 
USA Great Lakes states and in parts of Manitoba. In 
Northern Ontario (south of 51°N), these birds are 
considered rare transients but over the past decade 
have been sighted there with increasing frequency. 
Sightings of immatures in the last two years have led 
us to believe that there are Greater Sandhill Cranes 
breeding in Northern Ontario. We need more reports 



of sightings to estimate the population distribution 
and to pick an area of high concentration for a more 
intensive study of their biology, migration, and 
taxonomic verification. Please send reports, including 
the date, location, and number of birds to Paul 
Tebbel, Department of Zoology, University of West- 
ern Ontario, London, Ontario N6A 5B7. 



lUCN Prepares World Strategy 

A document designed to enable international 
conservation action to be directed much more 
effectively is now being prepared by lUCN (Interna- 
tional Union for Conservation of Nature and Natural 
Resources). 

Called A World Conservation Strategy, the docu- 
ment will identify the main ways in which species and 
ecosystems are depleted, degraded, or destroyed: 
define effective preventive or remedial action (by 
governments, intergovernmental bodies, and non- 
governmental bodies); and propose priorities for 
action. 

The three main functions of the strategy, which is 
funded by UNEP (United Nations Environmental 
Program) as part of the lUCN/UNEP ecosystem 
conservation project, are to provide UNEP, WWF 
(World Wildlife Fund), and other interested organiza- 
tions with a global appraisal and action plan for the 
protection, maintenance, and rational use of the 



planet's wild living resources; to enable lUCN to 
decide its program for 1979-1981; and to enable 
lUCN to advise WWF on the most effective ways of 
spending funds raised. 

A World Conservation Strategy will go into two 
drafts before being presented for approval by lUCN's 
14th General Assembly in late September 1978. 
Thereafter the strategy will be improved and updated 
from one general assembly to the next. 

By providing for the first time a global perspective 
on the many problems with which conservation is 
concerned and a means of ranking the most effective 
solutions to the priority problems, the strategy should 
enhance the capacities of lUCN. UNEP, and WWF to 
initiate action rather than simply to react to ad hoc 
requests for help. 



From lUCN Bulletin New Series 8(10): 59, 1977. 



Symposium — Natural Regulation of Wildlife Populations 



The Natural Regulation of Wildlife Populations is 
the theme of a symposium to be held in Vancouver, 
British Columbia on 10 March 1978. The theme will 
be discussed for individual species and species' groups 
by invited persons who have demonstrated through 
pubhshed research a knowledge of the issue. The 
symposium is part of the annual meeting of the 
Northwest Section of the Wildlife Society. The 



regular meeting of the section will be held on the two 
previous days, 8 and 9 March. For further informa- 
tion please contact F. Bunnell, Faculty of Forestry, 
University of British Columbia, Vancouver, British 
Columbia V6T iW5, or D. Eastman, Fish & Wildlife 
Branch, Ministry of Recreation and Conservation, 
Parliament Buildings, Victoria, British Columbia 
V8W2Z1. 



100 



The Canadian Field-Naturalist 



Vol. 92 



Wildlife Film Festival 

To encourage good wildlife film making, the 
University of Montana Student Chapter of The 
Wildlife Society (TWS) is sponsoring a Wildlife Film 
Festival. Films, all pertaining to wildlife, will be 
judged by a panel of internationally-recognized film 
makers. There are two categories, amateur (limited to 
Montana entries) and North American Professional 
produced in calendar year 1977. Awards and recog- 
nition will be presented. Based on the success of this 
year's festival, the chapter hopes to host an annual 



affair. 

Information, rules of eligibility, and application 
forms can be obtained by writing: Wildlife Film 
Festival, Wildlife Biology Program, University of 
Montana, Missoula, Montana 59812. 

The deadline for submission of applications is 1 
March 1978. Qualifying films will be judged and 
shown on 8-9 April 1978, at the University of 
Montana. 



Annual Meeting of Ontario Ornithologists 

The 1978 meeting will be held at the University of 
Guelph on 18 March 1978. Sessions will be held in 
Room 113, Physical Sciences Building; the registra- 
tion fee is $2. Two sessions are planned; 0930 to 1 200 h 
and 1300 to 1700 h. 

In the evening Room 168 of the Zoology Building 



has been reserved for informal gathering and dis- 
cussion. 

For further information please contact Alex L. A. 
Middleton or Vernon G. Thomas at the Department 
of Zoology, University of Guelph, Guelph, Ontario 
NIG 2W1 (telephone 519-824-4120). 



Book Reviews 



Zoology 



Animal Communication 

By Hubert and Mable Frings. 1977. Second Edition. 
University of Oklahoma Press, Norman, Oklahoma. 207 
pp., illus. Paper $6.25. 

When this book first appeared in 1964 it was greeted 
with enthusiasm because until then few biological 
popularists had come to grips with the engrossing 
subject of communication in animals. Hubert and 
Mable Frings, both connected with the University of 
Oklahoma, gathered their data from basic research in 
behavior, physiology, and ecology, organizing the 
work along functional lines so that if, for example, 
one wanted to learn about courtship and mating in 
mammals (one page), one could readily peruse these 
subjects in frogs and crabs too. The Frings were 
modest about their work: "With further knowledge, 
the provisional organization of communication pat- 
terns presented here — even possibly many of the 
"facts" — will undoubtedly need to be revised or 
discarded. It is stimulating to realize that impending 
discoveries may soon render the book itself 
outdated . . ." 

At present, of course, animal communications is 
recognized as an important field of study occupying 
the attentions of hundreds of biologists, so that in 
theory one should welcome a new "revised and 
enlarged" edition of Animal Communication. In fact, 
however, this edition is a great disappointment. The 
authors, far from being "stimulated" to realize that the 
first edition is outdated, have done a complete about- 
face. They write: "It would be easy ... to select a 
different set of examples to illustrate the uses of 
communication signals by animals. We feel, however, 
that little would be gained by doing so. The 
observations of 1964 remain valid in the late 1970's." 
What is easy was to leave the book as it was and 



merely add a 16-page chapter on recent research since 
1 963, which is what the Frings have done. What would 
have been an effort worth publishing would have been 
to rewrite the entire book in the light of exciting new 
discoveries. 

Not only is this book sadly dated, but it contains 
many errors which should have been corrected in a 
new printing. It is impossible to pinpoint them all 
since there are no literature citations in the text, and 
the bibliography, ahhough fairly comprehensive, is 
of a general nature. For one species with which I am 
familiar, however, I found gross inaccuracies. The 
worst was the statement that the male giraffe arouses 
the female by rubbing his neck along hers — thus 
necking with her. Necking in giraffe is a behavior 
pattern confined to males. The Frings claim that 
giraffe spread alarm by stampeding, giving this as an 
example of tactile communication. Yet giraffe do not 
touch each other when alarmed. Finally, they twice 
make the simplistic statement that the male giraffe 
determines a female's readiness to mate by tasting her 
urine. To describe the complex phenomenon of 
Flehmen in this way is to underestimate badly the 
interest and capacity of their readers. 

Publishers all too often re-issue non-fiction books 
without making certain they are really up-dated and 
worth republishing, a habit especially inexcusable in a 
university press. Worth it or not, the publishers can 
readvertize the work as something new and special, 
when in fact it is nothing of the sort. Animal 
Communication was perhaps worth buying in 1964, 
but 1 would not recommend this new edition. 



Anne Innis Dagg 



Box 747, Waterloo, Ontario N2J 4C2 



A Second Book of Canadian Animals 

By Charles Paul May. 1977. Macmillan, Toronto. 109 pp., 
illus. Paper $4.95. 

This 1977 paperback purports to be a new edition of 
the original 1964 book, but I can find no difference 
between the two. In any case the text is aimed at a 
seven- to ten-year-old child, so perhaps no up-dating 
was necessary. It describes briefly 26 mammals found 
in Canada, each pleasantly illustrated by John Crosby 
by a black-and-white pen drawing of an adult and of a Box 747, Waterloo, Ontario N2J 4C2 



juvenile. It is a companion to the 1962 A book of 
Canadian animals by the same author which describes 
an assortment of 28 different Canadian mammals. 
Both books are written in a lively manner which 
should appeal to a thoughtful child. 

Anne Innis Dagg 



101 



102 



The Canadian Field-Naturalist 



Vol. 92 



Ecology and Management of Animal Resouces, Ecologie de la zone de I'Aeroport 
International de Montreal 



J.R. Bider, E. Thompson, and R.W. Stewart. 1976. 
Les Presses de TUniversite de Montreal, Montreal. 246 pp. 
$12. 

As a title. Ecology and Management of Animal 
Resources is very misleading. It tends to suggest the 
book is a text on wildlife management which it 
definitely is not. The subtitle, Ecologie de la Zone de 
I'Aeroport International de Montreal, clarifies the 
book's topic somewhat, but not entirely. Basically this 
book is one in a series of reports all of which are 
concerned with the Mirabel airport project. 

The authors define their objective as "to supply data 
useful to a broad range of resource developers, 
including park naturalists as well as architects and 
land use planners." They define their approach as 
analytical and intended to "1) qualitatively and 
quantitatively describe the biotic community; 
2) develop a scale of values of parameters which 
could be used to describe the biotic richness of areas 
within the community; 3) provide information at the 
species level." Unfortunately two of the three steps in 
their approach are not satisfactorily met. 

The method of data collection for this study was the 
sand transect technique developed by the senior 
author (Bider 1968) and designed to measure animal 
activity. By the authors' own admission, the technique 
alone does not provide quantitative data ("Using the 
sand transect technique we measure the activity of the 
total population in space and time to be able to predict 
when, where, and relatively how many sightings might 
be made regardless of the numbers per unit area"). In 



the section of the text referring to individual animal 
species the lack of quantitative data is very apparent 
and a major weakness of the study. Perhaps trapping 
could have provided some better information on 
animal numbers. 

The sections dealing with birds are very weak. 
Granted, the authors state that this is a topic of 
another separate study; however, they did not indicate 
in the book's title that this work had been excluded. 

Reading through the text one wonders what effort 
was made to determine how representative the 
selected site was of the overall area. The authors 
clearly state "the procedure was to pick out small 
areas which contained all the major soil types found 
on the entire airport site and as many vegetation units 
as possible" and that "the results were used to 
synthesize a global view of animal activity on the 
entire expropriated territory." Are we to presume that 
extrapolation was a straight arithmetic proportion of 
area sampled versus area expropriated? 

Generally speaking if one is looking for a text on 
animal ecology this book is not recommended. For 
consultants interested in seeing another approach to 
animal inventory, the book may be of some interest. 

References Cited 

Bider, J.R. 1968. Animal activity in uncontrolled terrestrial 

communities as determined by a sand transect technique. 

Ecological Monographs 38: 269-308. 

Peter Croskery 
Ontario Ministry of Natural Resources. Ignace, Ontario 



BOTANY 



The Vascular Plants of South Dakota 

By Theodore van Bruggen. 1976. Iowa State University 
Press, Ames. 538 pp. Paper $7.95. 

Prior to the publication of this book, students 
interested in the plants of South Dakota had to "make 
do" with floras of adjacent regions. Now it is possible 
to identify the 1585 species known from this state, 
using a single volume. 

The book is organized in the fashion of a 
continuous dichotomous key in which the end of each 
dichotomy is an expanded species description to- 
gether with habitat, general locations within the state, 
flowering time, common names, and necessary 
synonomy. Students will find the short introduction 



which outlines the glacial history, geology, physiog- 
raphy, and climate most helpful in understanding the 
relationships of the flora of this very varied land. The 
text has been typewritten and has a ragged right-hand 
margin, two factors which give the volume a some- 
what unfinished look, but this does not detract from 
its usefulness. There are no distribution maps or 
illustrations, features which might be considered for a 
future edition. 

W. J. Cody 

Biosystematics Research Institute. Canada Department of 
Agriculture. Ottawa. Ontario KIA 0C6 



1978 



Book Reviews 



103 



Ontario Weeds 

By J. F. Alex and C. M. Switzer. 1976. Publication 505. 
Ontario Ministry of Agriculture and Food, Toronto. 200 
pp., 51 colored plates, 184 line drawings. $3.50. 

This new edition of Ontario Weeds is a completely 
revised work bearing little resemblance to its pre- 
decessors. With an attractively enlarged format (29.5 
X 21 cm) it includes reference to almost twice as many 
weed species as the previous edition. The key has been 
greatly expanded, a very large number of new 
drawings have been included, and although there are 
no longer any black-and-white photographs of seeds 
and seedlings, eight pages of color plates have been 
added. 

The primary purpose of the book is to allow the user 
to identify the more widely distributed or important 
weeds in Ontario. To this end, about 270 of the 500 or 
so weed species in the province are described and 195 
of these are illustrated by black-and-white line 
drawings. The drawings are of variable quality but 
nearly always give a realistic impression of the species 
involved. It is encouraging that it is the new drawings 
that are of the higher quality, often clearly illustrating 
features of diagnostic importance. The detail of the 
characteristic stem and leaf-base structure of the grass 
family is a particularly good example. On the other 
hand the new habit drawing of Veronica peregrina is 
hardly an improvement on its predecessor. 

As a means of identification the book is not without 
at least one serious shortcoming. Too often the key 
ends with the user having to distinguish amongst a 
large number of possible choices (in one case over 30 
species) with no other option than thumbing over the 



illustrations. The authors, moreover, do not seem very 
confident about the clarity of their keys, suggesting 
that users finding difficulty may have to restart "four 
or five times." In fact the characteristics used are for 
the most part readily discernible and should not 
present such severe difficulties even to the beginner. 

Errors are not numerous. One is the inclusion of the 
rather rare Cynanchum nigrum (see Pringle 1973, 
Canadian Field-Naturalist 87: 27-33) with an illus- 
tration that appears to be of C medium, the much 
commoner species of dog-strangling vine in Ontario. 
The seeds of white cockle and night-flowering catchfly 
are both oddly described as "grayish-orange"; both 
are, in fact, black when mature, the former with a gray 
bloom. 

This edition includes reference to giant foxtail 
{Setaria faberi — not faberii) with the remark that it 
"is not known to occur anywhere in Canada at 
present." Events, however, quickly overtook the 
authors, for prior to publication the species had 
already been collected in five separate localities in 
southern Ontario. Since then S. faberi has also been 
found to be a frequent weed in agricultural areas near 
Lake St. Clair. This striking demonstration of the 
constantly changing weed flora of Ontario, as of any 
other part of the world, makes us look toward future 
editions of this publication which will be as great an 
improvement on the present one as it is on its 
predecessor. 

J. McNeill 



Biosystematics Research Institute, Agriculture Canada, 
Ottawa, Ontario Kl A 0C6 



Vascular Plants of British Columbia — A descriptive resource inventory 



By Roy L. Taylor and Bruce MacBryde. 1977. University 
of British Columbia Botanical Garden Technical Bulletin 
Number 4. University of British Columbia Press, Van- 
couver. 754 pp. $28. 

Those who, from the title of this book, might have 
expected a classical flora with keys and descriptions, 
will be disappointed. This is a rather bulky, soft- 
covered, computer printout of data which has been 
gathered on the known vascular flora of British 
Columbia. 

The book is divided into nine sections: (1) intro- 
ductory material which lists contributors and con- 
sultants, a preface, and an introduction, directions on 
how to use the inventory, and a description of the 
computer program which was utilized, (2) the in- 
ventory, (3) an appendix of standard references, (4) an 
appendix of miscellaneous references, (5) an appendix 
of taxon to reference links, (6) an appendix of specific 



linked references, (7) an appendix of plant name 
authorities, (8) an example of the data form on which 
information to be input into the Flora of British 
Columbia project data base was accumulated, and (9) 
the index. 

The inventory has been divided into four sections: 
Pteridophyta, Pinophyta, Magnoliophyta-Dicotyle- 
dons, and Magnoliophyta-Monocotyledons. Within 
each of these sections the families, genera, and species 
are placed in alphabetical sequence. Thus the 
Asteraceae (Compositae) is found near the beginning 
of the Dicotyledons rather than at the end as in the 
Englerian System, which is followed in many floras. 
Cross references are provided for those searching for 
Leguminosae so that one might find the required entry 
under the Fabaceae, and for a genus like Chrysanthe- 
mum where the species found in the British Columbia 
flora are treated under Leucanthemum. 



104 



The Canadian Field-Naturalist 



Vol. 92 



In order to use the inventory readily, however, the 
reader must first become familiarized with the 
abbreviations which have been utilized under the 
headings of Distribution, Status, Duration, Habit, 
Sex, Flower Color, Fruit, Fruit Color, Flowering 
Time, Status of Chromosome Complement in British 
Columbia, Chromosome Base Number, Chromo- 
some Somatic Number Reported for British 
Columbia, Poisonous Status, Economic Status, 
Ornamental Value, and Endangered Status. This, for 
those who assembled the data, would have been easy, 
but for the individual who uses the work as an 
occasional reference it will be most annoying because 
frequent reference will have to be made to Appendix 6 
which is lost at the back of the book, and thus he may 
turn to the familiar floras of adjacent areas such as 
Flora of Alaska and Flora of the Pacific Northwest, 
rather than tackling this volume. 

The authors state that they have attempted to 
evaluate the taxonomic status of each of the 3 1 37 taxa 
that are presently known from British Columbia. This 



was indeed a formidable task. There is, however, no 
synonomy in the inventory, but for those who are 
searching for a familiar name not found, they may 
find a cross reference in the index. In the preface, the 
authors state that an illustrated, keyed field guide to 
the plants of British Columbia will be produced by the 
Botanical Garden of the University of British 
Columbia, and that later, a several-volume detailed 
flora will be produced by the British Columbia 
Provincial Museum. 

In the mean time, Vascular Plants of British 
Columbia — a descriptive resource inventory, will help 
link the areas treated by the Flora of Alaska and the 
Flora of the Pacific Northwest, and will serve "as a 
source of information for the evaluation of the 
country in relation to its future development and the 
effective utilization of its natural resources." 

William J. Cody 

Biosystematics Research Institute, Canada Department of 
Agriculture, Ottawa, Ontario KIA 0C6 



ENVIRONMENT 



Ecotours of the Trans-Canada Highway 

In 1972, the Canadian Forestry Service introduced 
a program to provide informative booklets to assist 
travellers to interpret the ecology of the landscapes 
along the Trans-Canada Highway. As the first 
Ecotour, a 20-panel, map-style folder published in 
1973 for the Ottawa to North Bay section, met a 
favorable public response, the project was continued. 
In 1974, a second Ecotour, covering the Rocky 
Mountain section from Calgary, Alberta to Golden, 
British Columbia, was issued as a 20-page booklet, 
265 X 165 mm. Since then, as contributions to the 
Man and the Biosphere Programme/ Canada, the 
Canadian Forestry Service has produced five more 
Ecotours: for Newfoundland West ( 1 975), Newfound- 
land East ( 1 975), Nova Scotia ( 1 976), Sault Ste. Marie 
to North Bay, Ontario (1976), and White River to 
Sault Ste. Marie, Ontario (1976). These latest are 16- 
page, full-color booklets, 204 X 228 mm. Ecotours are 
under production at each of the Canadian Forestry 
Service's regional forest research centers at Victoria, 
Edmonton, Sault Ste. Marie, Ste-Foy, Fredericton. 
and St. John's and at the Petawawa Forest Experi- 
ment Station. Eventually Ecotours will be available 
for the entire Trans-Canada Highway. 

The route covered by each Ecotour is divided into 
major, ecologically distinct, landscape types 



("Ecozones"). A map for each Ecozone or section 
shows the locations of interesting ecological features, 
which are in most cases identified by code numbers 
corresponding to those on relevant illustrations and 
text paragraphs, and the distances between these 
points of interest. The ecological scope is broad, 
including diverse features of natural history, both 
biological and geological, and of human history. 
Color and monochrome photographs, sketches, and 
paintings portray plants, animals, fossils, rocks, aerial 
views, landscapes, people, ships, and buildings. Lists 
of suggested readings complement most of these well- 
integrated brochures. 

The teams of scientists, writers, photographers, 
artists, and others that contributed to the production 
of this series have succeeded admirably in helping 
travellers understand the flora, fauna, people, 
scenery, and the forces that have shaped the land- 
scapes they see from their vehicles en route, at selected 
stops at points of interest, or on suggested detours. 
They merit much praise for producing attractive and 
information-packed booklets with very few dis- 
crepancies or errors. The scale for the first map in each 
Newfoundland Ecotour is clearly erroneous, but I 
noted only a single spelling error in the series. While 
some might not object to the inappropriate use of 



1978 



Book Reviews 



105 



"animals" for mammals, most naturalists would 
prefer that complete species names be given, e.g., for 
"partridge (ptarmigan)", as well as for the birds 
colorfully named locally as "tickle-asses," "stearins," 
and "sea pigeons" in Newfoundland. Although few or 
no metric measurements were given in earlier Eco- 
tours, their frequency has been increasing in later 
numbers, and SI and imperial units have equal 
prominence in the latest. 

The Canadian Forestry Service deserves con- 
gratulations for inaugurating this welcome educa- 
tional series of booklets for Canadian and visiting 
motorists, or indeed even for readers who stay at 
home. Unfortunately it seems that many travellers 
and naturalists, like myself until recently, are unaware 
of the existence and ready availability of Ecotours. 

Although the first Ecotour (Ottawa to North Bay) is 



out of print, all other numbers mentioned above are 
available without charge, in either French or English, 
from: Ecotours, Canadian Forestry Service. Environ- 
ment Canada, Ottawa, Canada KIA 0E7. 

I heartily recommend them to our readers both as 
prerequisites for planning trips on the Trans-Canada 
Highway and as indispensable companions en route. 
Their widespread use before and during trips, or even 
just at home or school should foster a marked increase 
in public awareness of the diversity, interest, and 
beauty of the natural and cultural features across this 
land. 

Donald A. Smith 

Department of Biology, Carleton University, Ottawa, 
Ontario KIS5B6 



A Concrete Look at Nature: Central Park (and other) glimpses 



By Eugene Kinkead. 1974. Quadrangle/ The New York 
Times Book Company, New York, xii, 242 pp. 

Despite the scoffing of some traditional zoologists, 
the study of wildlife in a modern urban setting seems 
to have an assured place at present. In this book, 
Kinkead writes mainly of Central Park, New York: 
840 acres (340 hectares) in central Manhattan. 

Whether bird-watching is still a safe pastime in 
Central Park is perhaps debatable, but in any case the 
author presents us with a glimpse of its avifauna. In 
the Preface, he tells us that "each year twelve to twenty 
species nest there," but no longer the Bobwhite and 
Wood Duck. In the opening chapter, the bird lists, 
with commentary, make fairly interesting reading, but 
"Baltimore oriole," "bronzed grackle," and "English 
sparrow" are outdated nomenclature. 

The next chapter, on meteors, is much more 
fascinating, with helpful hints on meteor-watching in 
the city. This topic may be somewhat unexpected in a 
book on urban nature, but the next essay, on Central 
Park squirrels, is not. Squirrels are at "an artificially 
high level here" and quite a challenge to census. 
Comments on their diet, densities, activity patterns, 
dens, litter size, and travel routes may be of interest 
even to the professional mammalogist. In this chapter, 
Kinkead introduces the only note on reptiles in the 
book — a brief account of a snake den in Central 
Park. 

Champion-size trees and a city conservation officer 
are the next two topics. Despite many statistics, the 
first is a fascinating topic, quite replete with lore and 
legend, such as the story of "the tree [which] grows in 
Brooklyn," as well as botanical data such as the effects 



of air pollution. The second subject I found not quite 
so interesting, despite vivid accounts of his "beat" in 
pet shops, restaurants, and other stores. 

"Big Rain" (Chapter 6) is again full of figures, but 
Kinkead does his best with these. The decline of the 
Eastern Bluebird (Chapter 7) provides an informative 
if depressing topic; the following one on "Bio- 
luminescence" (for example, of fireflies) is delightful. 
On the bluebird, the author aptly states "It is, in effect 
a bird of another era. In the vanished Currier and Ives 
landscape of an America of long ago . . ." He 
succinctly presents its status in New York City, along 
with a number of other highlights of its biology. The 
fireflies are described as "the pale, soft, disjointed 
artillery of summer's night," and their biology is also 
well explained as an amiazing but highly technical 
phenomenon. (Unfortunately not many scientific 
sources are given.) 

Five chapters of uneven interest close A concrete 
look at nature. Kinkead's book is lucidly written, and 
explanations are generally good. Flaws are minor. 
The waters of Central Park are cited as 12 in number 
on p. 228, but several are not shown on the endpaper 
maps. Other minor faults include some poor choices 
of common names for plants (e.g., "dogtooth violet,") 
use of cliches (e.g., "warm climes . . . biting frost 
. . . lofty reaches," or "critters"), occasional awkward 
phrasing, and overworked humor. The style contains 
much charm and some wit, however, so that at its best, 
it reminds one considerably of Edwin Way Teale's. 

C. A. Campbell 

421 King Street N, Waterloo, Ontario N2J 3Z4 



106 



The Canadian Field-Naturalist 



Vol. 92 



New Titles 



Zoology 



The American Robin. 1976. By L. Eiserer, Nelson-Hall, 
Chicago, 175 pp. $12.50. 

Analysis of vertebrate populations. 1977. By Graeme 
Gaughley. Wiley-Interscience, Somerset, New Jersey. 234 
pp., illus. $19.95. 

A biogeographical analysis of the Chihuahuan Desesrt 
through its herpetofauna. 1977. By David J. Morafka. 
Biogeographica. Volume 9. Junk, The Hague. viii + 314pp., 
illus. Dfl 95. 

The biology of insects. 1977. By C. P. Friedlander. Pica, 
New York. 189 pp., illus. $12.50. 

Birdland: the story ofa world famous bird sanctuary. 1976. 
By Len Hill and Emma Wood. Taplinger, New York. 144 
pp.. illus. $9.95. 

Birdwatcher's guide to wildlife sanctuaries. 1976. By 
Jessie Kitching. Arco, New York, .xv + 233 pp., illus. $8.95. 

Butterflies. 1976. By Jo Brewer. Abrams, New York. 176 
pp., illus. $18.50. 

The courtship of birds. 1977. By Hilda Simon, Dodd, 
Mead, New York. 190 pp., illus. 512.95. 

The evolution of national wildlife law. 1977. By M. J. 
Bean. United States Government Printing Office, 
Washington. 485 pp. $4.20. 

Fish population dynamics. 1977. Edited by J. A. Gulland. 

Wily-Interscience, Somerset, New Jersey. 372 pp. $27. 

Frogs. 1976. By Michael L. Tyler. Australian Naturalist 
Library. Collins, London. 256 pp., illus. $17.50. 

Handbook of freshwater biology. Volume 2, life history 
data on centrarchid fishes of the United States and Canada. 

1977. By Kenneth D. Carlander. Iowa State University 
Press. Ames, viii + 432 pp. $18. 

Inland fishes of California. 1976. By Peter B. Moyle. 
University of California Press, Berkeley. 405 pp., illus. $20. 

*An introduction to the aquatic insects of North America. 

1978. Edited by R. W. Merritt and K. W. Cummins. 
Kendall/Hall (Canadian distributor Burns and MacEa- 
chern, Toronto). Approx. 512 pp., illus. $18.95. 

Living new world monkeys (Platyrrhini) with an intro- 
duction to primates. Volume 1. 1977. By Philip Hersh- 
kovitz. University of Chicago Press, Chicago. 1136 pp., 
illus. $80. 

Manual of neotropical birds. Volume 1. Spheniscidae 
(penguins) to Laridae (gulls and allies). 1977. By Emmet 
R. Blake. University of Chicago Press, Chicago. 1674 pp., 
illus. $50. 



Mountain monarchs. Wild sheep and goats of the Hima- 
layas. 1977. By George B. Schaller. University of Chicago 
Press, Chicago. 432 pp., illus. $25. 

The order of wolves. 1976. Bv Richard Fiennes, Bobbs- 
Merrill, New York. 206 pp.. illus. $13.95. 

Sea mammals and reptiles of the Pacific coast. 1976. By 
Vinson Brown. MacMillan, New York, xvi + 265 pp., illus. 
$10.95. 

Watching birds: an introduction to ornithology. 1977. By 
R. F. Pasquier. Houghton Mifflin, Boston. 320 pp. $9.95. 

Ways of wildlife. 1977. Edited by Eleanor Horwitz. 
Citation/Scholastic, New York, xvi + 160 pp., illus. Paper 
$2.95. 

Wild birdwatchers I have known. 1977. By Gerry Bennett. 
G. Bennett, Woodbridge, Ontario. $3.75. 

Wildfowl 27. 1976. By G. V. T. Matthews and M. A. 
Ogilvie. Wildfowl Trust, Slimbridge, England. 176 pp. 
Paper £2.50. 

Wild mammals of New England. 1977. Johns Hopkins 
University Press (Canadian distributor Burns and Mac- 
Eachern, Toronto). 336 pp., illus. $30. 

Botany 

♦Atlas of the flora of the Great Plains. 1977. By Great 
Plains Flora Association. Coordinated by R. L. McGregor. 
Edited by T. M. Barkley. Iowa State University Press, 
Ames. 550 pp., illus. $25. 

A field guide to Pacific states wildflowers. Field marks of 
species found in Washington, Oregon, California and 
adjacent areas. A visual approach arranged by color, form 
and detail. 1976. By T. F. Niehaus. Illustrated by C. L. 
Ripper. Peterson Field Guide Series, 22. Houghton Mifflin, 
Boston. 

The forests of the sea: life and death on the continental 
shelf. 1976. By John L. Culliney. Sierra Club, San 
Francisco, x + 290 pp., illus. $9.95. 

Introduction to the history of mycology. 1976. By G. C. 
Ainsworth. Cambridge Universitv Press, New York, xi + 
359 pp., illus. $27.50. 

Medical botany: plants affecting man's health. 1977. By 
W. H. Lewis and M. P. F. Elvin-Lewis. Willy, New York 
xviii + 515 pp., illus. $27.50. 

*Orchid biology. Reviews and perspectives, 1. 1977. Edited 
bv Joseph Arditti. Cornell Universitv Press, Ithaca. 310 pp. 
$29.50. 

Trees and bushes of Europe. 1976. By O. Polunin. Oxford 
University Press, New York, xvi + 208 pp. $11.50. 



1978 



Book Reviews 



107 



Environment 

American environmental history. 1977. By J. M. Petulla. 
University of California Press, Berkeley. 400 pp. Cloth$15; 
paper $9.95. 

♦Arctic journey. Paintings, sketches and reminiscences of a 
vanishing world. 1977. By Peter Buerschaper. MacMillan, 
Toronto. 126 pp. $14.95.' 

Big biology. The US/ IBP. 1977. By W. Frank Blair. 
US/ IBP Synthesis Series, Volume 7. Dowden, Hutchinson 
and Ross, Stroudsburg, Pennsylvania, x + 262 pp. $14.95. 

Coastal ecosystem management. A technical manual for the 
conservation of coastal resources. 1977. By John R. 
Clark. Wiley-Interscience, Somerset, New Jersey. 928 pp., 
illiis. $38.50. 

The coastline. A contribution to our understanding of its 
ecology and physiography in relation to land-use and 
management and the pressure to which it is subjected. 1977. 
Edited by R. S. K. Barnes. Wiley-Interscience, Somerset, 
New Jersey. 356 pp. $28.50. 

The cult of the wild. 1977. By B. Rensberger. Drawing by 
B. Eraser. Anchor/ Doubleday, Garden City, New York, 
viii + 280 pp. $7.95. 

Dimensions of ecology. 1977. By J. L. Richardson. Ox- 
ford University Press, New York, xiv + 412 pp., illus. $16. 

The endless chain of nature: experiment at Hubbard Brook. 

1976. By P. P. Sturges. Westminster, Philadelphia. 159 
pp., illus. $7.95. 

Extinction is forever. Threatened and endangered species of 
plants in the Americas and their significance in ecosystems 
today and in the future. 1977. Edited by G. T. Prance and 
T. S. Elias. Proceedings of a symposium. New York, May 
1976. New York Botanical Garden, Bronx. vi+ 438 pp., 
illus. Paper $20. 



Freshwater biology. 1977. By L. G. 
New York. 167 pp., illus. $12'50. 



Willoughby. Pica, 



tFundy tidal power and the environment. 1977. Edited by 

G. R. Daborn. Proceedings of a workshop on the environ- 
mental implications of Fundy Tidal Power, Wolfville, Nova 
Scotia, November 1976. Acadia University Institute Publi- 
cation Number 28, Wolfville. v + 303 pp., illus. Paper $10 
prepaid: $11.50 otherwise. 

A guide to nature in winter: northeast and north central 
North America. 1976. By Donald W. Stokes. Little, 
Brown, Boston. 374 pp., iilus. $8.95. 

Mainstreams of biology. 1977. By G. B. Moment and 



H. M. Habermann. Oxford University Press, New York, 
xii + 426 pp., illus. $12.95. 

Recovery and restoration of damaged ecosystems. 1977. 

Edited by J. Cairns, Jr., K. L. Dickson, and E. E. Herricks. 
University of Virginia Press. Charlottesville. 448 pp. S20. 

Trails to nature's mysteries: the life of a working naturalist. 

1977. By Ross E. Hutchins. Dodd, Mead, New York. 223 
pp., illus. $6.95. 

Miscellaneous 

The collected papers of Charles Darwin. 1977. Edited by 
Paul H. Barrett. University of Chicago Press, Chicago. 
Volume 1, xviii + 278 pp., illus; volume 2, viii + 326 pp., illus. 
Set $40. 

Concepts and methods of biostratigraphy. 1977. Edited 
by E. G. Kauffman and J. E. Hazel. Dowden, Hutchinson 
and Ross, Stroudsburg, Pennsylvania, xiv + 658 pp., illus. 

$35. 

Energy book #2: more natural sources and backyard 
applications. 1977. Edited by John Prenis. Running Press, 
Philadelphia. 125 pp., illus. Paper $5. 

A fish and vegetable grower for all seasons. 1977. By R. E. 
Huke and R. W. Sherwin, Jr. Norwich Publications, 
Norwich. Vermont, iv + 126 pp., illus. Paper $4.95. 

*Forest soils: properties and processes. 1977. By K. A. 
Armson. University of Toronto Press, Toronto. $22.50. 

Geomorphology and time. 1977. By J. B. Thornes and D. 
Brunsden. Halsted (Wiley), New York, xvi + 208 pp., illus. 
$12.95. 

jScientists confront Velikovsky. 1977. Edited by Donald 
Goldsmith. Cornell University Press, Ithaca. 183 pp. $8.95. 

A vanishing world: the dinosaurs of western Canada. 1977. 

By Dale W. Russell. Photography by Susanne M. Swibold. 
Paintings by Eleanor M. Kish. National Museum of 
Natural Sciences, Ottawa. 144 pp., illus. $12.95. 

*Weather almanac. A reference guide to weather, climate 
and air quality in the United States and its key cities 
comprising statistics, principles and terminology. 1977. 
Edited by J. A. Ruffner and F. E. Blair. 2nd edition. Gales, 
Detroit. 728 pp. $25. 

Winter touring: cross-country skiing and snowshoeing. 

1977. By Clayne R. Jensen. Burgess, Minneapolis. 163 pp., 
illus. Paper $7.95. 

♦assigned for review 
+available for review 



Instructions to Contributors 



Content 

77?^ Canadian Field- Naturalist is a medium for publica- 
tion of original scientific research papers in all fields of 
natural history that have relevance to Canada. As the journal 
has a flexible publication policy, items not covered in the 
traditional sections (Articles, Notes, Letters, News and 
Comment, and Book Reviews) can be given a special place 
provided they are judged suitable. Naturalists are also 
encouraged to support local natural history publications. 

Manuscripts 

Please submit, in either English or French, three complete 
manuscripts written in the journal style. The research 
reported should be original. It is recommended that authors 
ask qualified persons to appraise the paper before it is 
submitted. Also authors are expected to have complied with 
all pertinent legislation regarding the study, disturbance, or 
collection of animals, plants, or minerals. 

Type the manuscript on standard-size paper, if possible 
use paper with numbered lines, double-space throughout, 
leave generous margins to allow for copy marking, and 
number each page. For Articles, provide a running head, a 
bibliographic strip, an abstract, and a list of key words. 
These items are optional for Notes. Generally words should 
not be abbreviated but use SI symbols for units of measure. 
Underline only words meant to appear in italics. The names 
of authors of scientific names should be omitted except in 
taxonomic manuscripts or other papers involving nomen- 
clatural problems. Authors are encouraged to use "proper" 
common names (with initial letters capitalized) as long as 
each species is identified by its scientific name once. 

Although we prefer the names ofjournalsinthe Literature 
Cited to be written out in full, these may be abbreviated 
following the Bibliographic Guide For Editors & Authors, 
The American Chemical Society, Washington, D.C. (1974). 
Unpublished reports should not be cited here. Next list the 
captions for figures (numbered in arabic numerals and typed 
together on a separate page) and present the tables (each 
titled, numbered consecutively in arabic numerals, and 
placed on a separate page). Mark in the margin of the text 
the places for the figures and tables. 



Extensive tabular or other supplementary material not 
essential to the text, typed neatly and headed by the title of 
the paper and the author's name and address, should be 
submitted in duplicate on letter-size paper for the Editor to 
place in the Depository of Unpublished Data, CISTI, 
National Research Council of Canada. Ottawa, Canada 
KIA 0S2. A notation in the published text should state that 
the material is available, at a nominal charge, from the 
Depository. 

The CBE Style Manual, 3rd edition (1972) published by 
the American Institute of Biological Sciences, is recom- 
mended as a guide to contributors. Webster's New Inter- 
national Dictionary and le Grand Larousse Encyclopedique 
are the authorities for spelling. 

Illustrations — Photographs should have a glossy finish and 
show sharp contrasts. Photographic reproductions of line 
drawings, no larger than a standard page, are preferable to 
large originals. Prepare line drawings with India ink on good 
quality paper and letter (don't type) descriptive matter. Write 
author's name, title of paper, and figure number on the lower 
left corner or on the back of each illustration. 

Special Charges 

Authors must share in the cost of publication by paying 
$45 for each page in excess of six journal pages, plus $5 for 
each illustration (any size up to a full page), and up to $45 per 
page for tables (depending on size). Reproduction of color 
photos is extremely expensive; price quotations may be 
obtained from the Business Manager. When galley proofs 
are sent to authors, the journal will solicit on a voluntary 
basis a commitment, especially if grant or institutional funds 
are available, to pay $45 per page for all published pages. 
Authors may also be charged for their changes in proofs. 

Limited journal funds are available to help offset publica- 
tion charges to authors with minimal financial resources. 
Requests for financial assistance should be made to the 
Editor when the manuscript is submitted. 

Reprints 

An order form for the purchase of reprints will accompany 
the galley proofs sent to the authors. 



Reviewing Policy of The Canadian Field-Naturalist 



Manuscripts submitted to The Canadian Field-Naturalist 
are normally sent for evaluation to an Associate Editor (who 
reviews it himself or asks another qualified person to do so), 
and at least one other reviewer, who is a specialist in the field, 
chosen by the Editor. Authors are encouraged to suggest 
names of suitable referees. Reviewers are asked to give a 
general appraisal of the manuscript followed by specific 



comments and constructive recommendations. Almost all 
manuscripts accepted for publication have undergone 
revision — sometimes extensive revision and reappraisal. The 
Editor makes the final decision on whether a manuscript is 
acceptable for publication, and in so doing aims to maintain 
the scientific quality and overall high standards of the 
journal. 



TABLE OF CONTENTS (concluded) 

Book Reviews 

Zoology: Animal communication — A second book of Canadian animals — Ecology and 101 

management of animal resources, Ecologie de la zone de I'Aeroport International de Montreal 

Botany: The vascular plants of South Dakota — Ontario weeds — Vascular plants of British 102 

Columbia - a descriptive resource inventory 

Environment: Ecotours of the Trans-Canada Highway — A concrete look at nature: Central Park 104 

(and other) glimpses 

New Titles 106 

Mailing date of previous issue 28 February 1978. 



THE CANADIAN FIELD-NATURALIST Volume 92, Number 1 1978 

Articles 

Rearing Atlantic Salmon {Salmo salar) in fishless lakes of the 

Matamek River System, Quebec David M. Rimmer and G. Power 1 

Species-area relationships for vascular plants of some St. Lawrence River Islands 

J. McNeill and W. J. Cody 10 

Evaluation of the winter range of White-tailed Deer in Point Pelee 

National Park, Ontario John B. Theberge 19 

Birds of the coastal zone of Melville Island, 1973-1975 Lynda S. Maltby 24 

Above-ground biomass of vascular plants in a subarctic James Bay salt marsh 

Walter A. Glooschenko 30 

Food habits of three sympatric species of Insectivora in western Washington 

Carol J. Terry 38 

Nesting behavior and food habits of Parasitic Jaegers at Anderson River Delta, 

Northwest Territories Marilyn Martin and Thomas W. Barry 45 

Reproductive success of Herring Gulls on Granite Island, northern Lake Superior, 

1975 and 1976 John P. Ryder and Timothy R. Carroll 51 

Bird use of a Beaufort Sea barrier island in summer Douglas Schamel 55 

Recoveries of Saskatchewan-banded Great Horned Owls C. Stuart Houston 61 

Notes 

Food of Ringed Seals and Bowhead Whales near Point Barrow, Alaska 

Lloyd F. Lowry. Kathryn J. Frost, and John J. Burns 67 

Birds and mammals as passive transporters for algae found in lichens Craig S. Scharf 70 

Winter predation by Black-capped Chickadees and Downy Woodpeckers on inhabitants of the 

Goldenrod Ball Gall Lyanne Schlichter 71 

The status of Lythrum alatum (Lythraceae) in Canada William J. Cody 74 

Prey utilized by Merlins nesting in shortgrass prairies of southern Alberta Keith Hodson 76 

Northern Leopard Frogs and Bullfrogs on Vancouver Island David M. Green 78 

Northern Fulmar breeding range extended to Baccalieu Island, Newfoundland 

W. A. MoNTEVECCHi. E. Blundon, G. Coombes, J. Porter, and P. Rice 80 

Life history observations on the nudibranch mollusc Onchidoris bilamellata in the 

intertidal zone of Nova Scotia J. Sherman Bleakney and Constance L. Saunders 82 

Additions to the flora of Alberta and new records 

Sylvester Smoliak and Alexander Johnston 85 

European Flounder {Platichthys flesus) captured in Lake Erie, Ontario 

A. R. Emery and G. Teleki 89 

Site and seasonal variations in food of wolves, Algonquin Park, Ontario 

John B. Theberge, Sebastian M. Oosenbrug. and Douglas H. Pimlott 91 

Durability of tree holes used by Buffleheads Anthony J. Erskine 94 

Range extensions to the flora of the eastern Canadian Arctic 

J. R. JOTCHAMandS. P. VaNDER KLOET 95 

News and Comment 97 

concluded on inside back cover 

ISSN 0008-3550 



MUS. COMP. 200U 



The CANADIAN 'IZT 
FIELD-NATURALIST* 



HARVARD 
ITY 



Published by THE OTTAWA FIELD-NATURALISTS' CLUB, Ottawa, Canada 



/. 






f'"*^: " ' ^^ 



-I 



K '^^ 











Volume 92, Number 2 



•^^i'Al:..' 



April-June 1978 



The Ottawa Field-Naturalists' Club 

FOUNDED IN 1879 

Patrons 

Their Excellencies the Governor General and Madame Jules Leger 

The objectives of this Club shall be to promote the appreciation, preservation, and conservation of Canada's natural 
heritage; to encourage investigation and publish the results of research in all fields of natural history and to diffuse 
information on these fields as widely as possible; to support and cooperate with organizations engaged in preserving, 
maintaining, or restoring environments of high quality for living things. 

Those wishing to communicate with the Club should address correspondence to: The Ottawa Field-Naturalists' Club, 
Box 3264. Postal Station C, Ottawa, Canada KlY 4J5 

The Canadian Field-NaturaUst 

77?^ Canadian Field-Naturalist is published quarterly by The Ottawa Field-Naturalists' Club with the assistance of a 
contribution from the National Research Council of Canada. Opinions and ideas expressed in this journal are private and do 
not necessarily reflect those of The Ottawa Field-Naturalists' Club or any other agency. 

Editor: Lorraine C. Smith 
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Associate Editors 

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Second Class Mail Registration No. 0527 — Return Postage Guaranteed. 

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Most back numbers of this journal and its predecessors. Transactions of The Ottawa Field-Naturalists' Club. 1879- 
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Address manuscripts on birds to the Associate Editor for Ornithology: 

Dr. A. J. Erskine, Canadian Wildlife Service, Box 1590, Sackville, New Brunswick EOA 3C0 

All other material intended for publication should be addressed to the Editor: 

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Urgent telephone calls may be made to the Editor's office (613-996-5840), the office of the Assistant to the Editor (6 1 3-23 1 - 
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Cover: Woodchuck photographed 17 August 1965 by Donald A. Smith, on Carleton University campus, Ottawa, Ontario. 
See article on page 128. 



The Canadian Field-Naturalist 



Volume 92, Number 2 



April-June 1978 



Changes in Aspen Parkland Habitats Bordering 
Alberta Sloughs 



Gray Merriam 

Department of Biology, Carleton University, Ottawa, Ontario KIS 5B6 

Merriam, Gray. 1978. Changes in aspen parkland habitats bordering Alberta sloughs. Canadian Field-Naturalist 92(2): 
109-122. 

Aspen parkland habitats within 50 m of 913 sloughs in 74 quarter sections throughout Alberta's aspen parkland were 
mapped in the field and a subsample of 398 sloughs was compared with 1945-1949 airphotos. Between 1945-1949 and 1974 
woody borders were reduced around 80% of sloughs in the subsample and eliminated completely from 32%. The average loss 
of border habitats was 1 .0 ha per slough or 11.7 ha per quarter section. Average losses per slough were 32% of young aspen, 
9% of older aspen, 68% of willows, and 74% of Wolf Willow, Buckbrush, and other shrubs taken together. These are net losses 
and are not explainable by maturation. The modal index of heterogeneity of habitats bordering sloughs was low throughout 
the parkland, and in some areas few sloughs had even moderate border heterogeneity. Existing heterogeneity and recent 
changes in slough border habitats both are strongly influenced by agricultural practices. Changes reported here have altered 
the basic nature of the habitat mosaic of Alberta's aspen parkland. 

Key Words: agriculture, Alberta, aspen parkland, heterogeneity, sloughs, waterfowl. 



Aspen parkland developed as an irregular 
mosaic of aspen groves and Rough Fescue parks 
mainly on poorly drained till between the mixed 
prairie and the boreal forest. 

The parkland and its sloughs have been 
valuable habitats for many wild species, plant 
and animal, game and non-game (Bird 1961; 
Bird and Bird 1967). A particularly large 
proportion of North American ducks is pro- 
duced in habitats associated with parkland 
sloughs. During dry years, the more stable water 
area of the parkland accommodates a reserve of 
breeding waterfowl that stabilizes prairie duck 
production (Stoudt 1971). 

The aspen parkland is young and dynamic 
(Bailey and Wroe 1974; Kiel et al. 1972; 
Johnston and Smoliak 1968; Bird 1961) but its 
historical development is not fully understood 
(Coupland 1950; Hansen 1949; Moss and 
Campbell 1947). The clonal reproduction of 
aspen (Horton and Maini 1964) clearly was an 
important factor throughout the history of the 
parkland. Fire (Bailey and Wroe 1974; Bird 



1930, 1961; Moss 1932) and mechanical disturb- 
ances (Roe 1939) may have been important at 
particular times. Recent technological and 
economic changes have made agriculture a 
major force of change in the parkland. Changes 
in the parkland probably were most rapid during 
the period of settlement after World War I but 
the changes during the quarter century after 
World War II were both extensive and intense 
(Kiel et al. 1972; Lodge 1969; Bird 1961) (see 
Figure 1). 

About a quarter century ago the aspen 
parkland occupied about 222 000 km- of which 
about 52 000 km^ were in Alberta (Moss 1932; 
Moss and Campbell 1947). The area of Alberta 
parkland has been changed substantially by 
agricultural development within the parkland 
mosaic. Lodge (1969) reported that about 
1000 km^ per year within the Alberta parkland 
was being removed just for conversion to 
improved pasture. These figures suggest that the 
parkland is still subject to important changes but 
there is little knowledge of the extent, nature or 



109 



no 



The Canadian Field-Naturalist 



Vol. 92 




Figure L Much of the Central parkland is now an agricultural mosaic composed of quarter sections under diverse land 
management. 



rate of recent changes to aspen groves and 
habitats bordering parkland sloughs. The pres- 
ent study was undertaken to assess changes that 
have taken place in slough borders since World 
War II and to provide baseline descriptions 
against which future changes can be measured. 

Methods 

Study Area 

Seventy-four quarter sections, each 64.75 ha 
(or 0.5 X 0.5 mi), were selected from 200 
quarters previously chosen randomly from 
Alberta's black soil zone by Goodman and Pryor 
(undated. A preliminary study of the methods 
and rates of alteration of waterfowl habitat in 
the black soil zone of western Canada. Un- 
published report", Canadian WildHfe Service, 
Edmonton, Alberta, 55 pp.). These 74 quarter 



sections met two criteria: ( 1 ) they had more than 
one slough, and (2) they were photographed 
from the air during the 1970 study. The majority 
of 913 sloughs studied were less than 0.2 ha 
(0.5 acres), over 700 were less than 0.4 ha, and 
only a few exceeded 2 ha (5 acres) but large 
sloughs were not excluded from the sample. 
Figure 2 shows the distribution of this sample 
throughout the Alberta aspen parkland. 

Field Mapping 

A base map was prepared for each quarter 
section from vertical airphotos, 5.7 X 5.7 cm, 
taken in the 1970 study. Negatives of those 
photographs were enlarged optically onto graph 
paper (25 X 25 cm) to a scale of 1:3706. All 
important landmarks, vegetation, and land use 
boundaries and slough features, as they ap- 
peared in 1970, were traced from the projected 



1978 



Merriam: Sloughs and Aspen Parkland, Alberta 



111 



Cold Loke« 



,:::;il0^0Mm^^^^M^, 




100 mi 

r- 



icine 
Hat 



100 Km 



Figure 2. Distribution of 74 quarter sections studied in tlie field (circles and triangles) and those also studied from 
1945-1949 airphotos (triangles only). Boundaries for three regional subsamples and approximate limits of Alberta 
parkland also are shown. 



image onto 1-mm graph paper. These base maps 
were used in the field to map vegetation and land 
use boundaries at 1 mm = 3.7 m and to note 
changes since 1970. Figure 3 is an example of a 
completed field map. 

Vegetation Types 

Major vegetation types within 50 m of the 
edge of each slough were mapped to char- 
acterize the habitats bordering the sloughs. 
Woody vegetation bordering sloughs was usu- 
ally dominated by Trembling Aspen {Populus 



tremuloides). Populus balsamifera balsamifera 
and ssp. trichocarpa (Brayshaw 1965) are not 
separated from P. tremuloides. 

Findings of Maini (1960) and Horton and 
Maini (1964) suggested that growth, senescence, 
and rejuvenation of aspen groves are not usually 
strict functions of age or of diameter (evident 
also in definitions, below). A classification of 
stand maturity was devised to give useful 
inventories of existing habitat conditions in 
slough borders. Four aspen maturity classes 
were used: (1) PO IV, overmature stands with 



112 



The Canadian Field-Naturalist 



Vol. 92 




WHEAT 





I -J— SH.MSH. 
\. / >57o 



OPEN 



SH. MSH. 
<57o_^ 

no woody 



c^ 



no woody 



TILLED 
dry 



Figure 3. Composite map of part of a quarter section to illustrate methods of field mapping and indexing heterogeneity. 
Slough types: shallow marsh, deep marsh, wet meadow, and percent open water area. Vegetation: PO I, PO II, 
PO III, PO IV — aspen maturity classes; Wi — willows; CN — natural clearing. Coarse dashed line, land-use 
boundary. Transects for indexing heterogeneity are drawn on sloughs 3 and 6. On slough 3, the N, W, S, and E 
transects score 3, 1.2, and 2 for 50 m out from water's edge (solid line). For slough 6 the scores are 3, 1 , 1 , and 2 in the 
same order. The heterogeneity index is 8 for slough 3, and 7 for slough 6. 



1978 



Merriam: Sloughs and Aspen Parkland, Alberta 



113 



butt rot or rotting and falling limbs or tops, 
diameter at breast height (dbh) > 12 cm, 
averaging > 19 cm, ages > 32 yr, averaging 

> 50; (2) PO III, prime maturity, dbh > 5 cm, 
averaging near 11 cm, ages > 16 yr, averaging 

> 26 yr; (3) PO II, immature, dbh > 3 cm, 
averaging > 5 cm, usually > 6 yr, averaging 
near 12; (4) PO I, suckers or saplings up to 3 m 
tall or 3 cm dbh. Dead aspen also was recorded 
in these classes. These maturity classes were 
assigned by visual inspection during field 
mapping; ages and diameters were not measured 
on mapped stands. Defining measurements 
given above were taken from 130 trees in 
representative stands. 

Willows (Salix spp.) were common in slough 
borders. They were mapped and noted as live or 
dead but not designated by species. 

Upland shrubs that were mapped for 50 m 
back from every slough were Wolf Willow 
(Elaeagnus commutata), Buckbrush (Symphori- 
carpos occidentalis), roses {Rosa spp), rasp- 
berries (Rubus spp.), and Saskatoons (Amel- 
anchier alnifolia). These five species (hereafter 
called "shrubs") were analyzed as a group. 
Adjacent agricultural land use also was mapped. 
Plant names follow Moss (1959). 

Slough Types and Sizes 

Aquatic and semi-aquatic vegetation was not 
mapped but was the basis for the classification of 
each slough. Six slough types were recognized 
(see, for example. Figure 3) (cf., Stewart and 
Kantrud 1969, 1971): (1) Tilled — cultivated or 
hay or grain; (2) Low Prairie — all grasses and 
forbs with no semi-aquatics or sedges, may have 
been tilled previously; (3) Wet Meadow — 
grasses and sedges, central portion may be 
dominated by semi-aquatics, may have been 
tilled previously; (4) Shallow Marsh — few or no 
grasses in central portion, sedges usually 
important, Polygonum, Eleocharis, Juncus, 
Slum, Ranunculus, Alisma, or Sparganium 
usually among the emergents, Lemna and 
Utricularia often in open water; (5) Deep Marsh 
— sedges not important in deepest portion, 
Typha or Scirpus often present, Potomageton, 
Ceratophyllum, Myriophyllum, Utricularia, 
Ranunculus may be present in open water; (6) 
Open Pond — not characterized by vegetation, 
usually to 5% cover. Low prairies and wet 
meadows were divided into wet or dry. Marshes 



were subclassed by area of open water into dry, 
< 5%, 5% to 50%, 50% to 95% or > 95%. 

Boundaries of tilled sloughs, low prairies, and 
wet meadows followed the poorly drained basin 
as indicated by vegetation types. Boundaries of 
sloughs with woody borders were drawn 
through the willow ring. When lacking woody 
borders, the shallow marshes, deep marshes, and 
open ponds were bounded through the zone of 
semi-aquatic vegetation with reference to topog- 
raphy and drainage changes. Water levels were 
abnormally high in 1974 and often exceeded 
slough boundaries. Slough sizes were measured 
from field maps by dot grid planimeter. 

Habitat Heterogeneity 

A heterogeneity index was devised to sum- 
marize the mapped descriptions of habitats 
bordering the sloughs and to permit their 
quantitative comparison. Crossed transects were 
laid over each slough on the field maps with four 
arms radiating N, S, E, and W for 50 m from the 
slough edge (see Figure 3). These arms were 
treated as four separate transects. Each mapped 
vegetation type, land-use type or adjacent slough 
cut by each transect was recorded in order from 
slough edge to transect end. Thus transect N 
described the S-facing slough border, etc. If a 
transect went off the quarter section before it 
reached 50 m from the slough, its record was 
terminated with "off quarter" and excluded from 
the analysis. 

Total number of occurrences of vegetation 
types, land-use types, and adjacent sloughs 
intercepted by each of the four transect arms was 
used to index the heterogeneity of habitats 
around each slough. Dead woody vegetation 
was included with live of the same type. If a 
habitat type repeated itself along a transect arm, 
say as habitats 1 and 3 in a sequence, it scored 
twice. The mean of the scores for the transect 
arms that did not go "off quarter" was the 
heterogeneity index for that slough. For sloughs 
that were not on the quarter section boundary, 
an index of 1 would mean one habitat type on 
each transect arm, an index of 2 would mean two 
habitat types on each transect arm or five on one 
arm and one on each of three others, etc. The 
heterogeneity index can be subdivided to show 
how much of the heterogeneity was due to (1) 
woody vegetation (aspen + willows), (2) natural 
habitats (woody vegetation + shrubs and 



114 



The Canadian Field-Naturalist 



Vol. 92 



roses + non-agricultural clearings + any adja- 
cent sloughs), and (3) agricultural land uses. 

Slough borders also were characterized by the 
degree to which the aspen or willow border (not 
"shrubs") encircled each slough. This was 
indexed by counting the number of transect 
arms which crossed aspen or willow habitats 
provided only that the vegetation units actually 
were connected together to form a slough 
border. These index values were grouped into 
Smith's (1971) original classes. Class 1 ("open") 
had scores of or 1 , class 2 ("half closed") scored 
2, and class 3 ("closed") scored 3 or 4. 

Regional Comparison 

After field work was completed, in order to 
compare different types of parkland, three 
regions were defined as shown in Figure 2. These 
are "Central" (West of Meridian (M) 4, Town- 
ship (T) >45, Range (R) < 19), "Southern 
Edge" (M = 4, T < 32, R < 28), and "Willow- 
Aspen" (M = 5, T ^ 34, R < 5). Regions were 
defined to show whether these subsamples 
contained different types of habitats associated 
with the sloughs. Therefore regional samples 
were defined to fall clearly within each region 
and to avoid the boundaries. Consequently some 
sloughs that are included in the total sample of 
913 are not included in the total of these regional 
samples (655). The total sample (913) is used 
wherever possible but regional samples are used 
for comparisons that demonstrate regional 
differences in woody slough borders. 

Habitat Changes 1945-1949 to 1974 

Airphotos were available from 1945-1949 for 
398 sloughs which had woody borders then and 
also were studied in 1974. Data from these 
airphotos were compared with 1974 field data 
for the same sloughs to measure changes in 
vegetation during the 25 to 29 years following 
World War II. This sample was defined solely by 
the availability of airphotos from 1945-1949 at 
1 : 1 5840 scale, and the resulting sample distribu- 
tion means that changes revealed by this 
comparison apply primarily to the area north of 
Hanna (Figure 2). 

Data for 1945-1949 were obtained by air- 
photo interpretation. Vegetation types were (a) 
PO I and II, (b) PO III and IV, (c) willows, (d) 
Wolf Willow, Buckbrush, and roses. Grouping 
into these more inclusive categories reduced the 



chance of interpretation error and still gave 
satisfactory comparisons with 1974 data. Inter- 
pretation of these vegetation types was based on 
crown diameter, height, texture, and tone. Since 
both aspen types usually appeared on every 
photo, their interpretation also was com- 
parative. 

Areas of each vegetation type were measured 
by dot grid planimeters. One was scaled for the 
1945-1949 airphotos, the other for the 1974 
maps. Both measured in units of 0.16 ha 
(0.395 acres). 

Some factors causing change in parkland 
slough borders also were evaluated. Clearing of 
aspen or willow since 1970 was recorded in the 
field and by comparing 1970 photos with 1974 
field maps. Clearing was recorded as extensive 
(large areas bulldozed or many slough borders 
totally removed), or minor (fence lines bulldozed 
or a few slough borders trimmed back), or 
moderate if between these extremes. Use of 
herbicide for clearing was recorded similarly. 
Agricultural intensity was rated in five classes 
for each quarter section. Intensity ratings were 
based on amount, type, and distribution of 
machinery, livestock, woody and weedy vege- 
tation, and tillage. Other developments, such as 
gas or oil rigs and lines, roads, buildings, 
drainage and filling operations were recorded 
where they affected sloughs or their borders. 

Results 

Distribution and Abundance of Slough Types 
The abundance of all slough types in each 
region of Alberta parkland and in the total 
sample is given in Table 1. Tilled sloughs are 
uncommon in the Willow-Aspen because it is 
primarily rangeland; they are most common in 
the Southern Edge owing to intensive agri- 
culture and easily tilled slough types. Wet 
meadows and low prairies are most common in 
the Southern Edge and Willow-Aspen but these 
areas were nearly all dry in 1974, and in those 
same regions shallow marshes commonly had 
less than 5% open water (more than 95% 
vegetative cover). Open ponds and deep marshes 
were much less frequent in the Southern Edge 
and the Willow-Aspen. 

Table 2 reduces the slough types to five so that 
their occurrence in five size classes can be 
examined by region. Deep marshes (Central 



64(7.0) 


27(5.8) 


3(3.2) 


3(3.0) 


22(2.4) 


5(1.1) 


0(0) 


0(0) 


50(5.5) 


37(8.0) 


0(0) 


0(0) 


46(5.0) 


28(6.1) 


1(1.1) 


0(0) 


4(0.4) 


3(0.6) 


0(0) 


0(0) 


18(2.0) 


6(1.3) 


0(0) 


0(0) 


71(7.8) 


48(10.4) 


1(1.1) 


6(6.1) 


101(11.1) 


69(14.9) 


3(3.2) 


5(5.1) 


165(18.1) 


107(23.2) 


1(1.1) 


13(13.1) 


52(5.7) 


10(2.2) 


6(6.4) 


9(9.1) 


23(2.5) 


17(3.7) 


1(1.1) 


0(0) 


176(19.3) 


60(13.0) 


34(36.1) 


49(49.5) 


3(0.3) 


2(0.4) 


0(0) 


1(1.0) 


33(3.6) 


2(0.4) 


15(15.9) 


10(10.1) 


85(9.3) 


41(8.9) 


29(30.8) 


3(3.0) 



1978 Merriam: Sloughs and Aspen Parkland, Alberta 115 

Table 1 — Frequency distribution of slough types for all sloughs' examined and for three parkland regions^ 

All Southern Willow- 

Slough type sloughs, Central, Edge, aspen, 

(vegetation, open water) no. (%) no. (%) no. (%) no. (%) 

Open pond 
Deep marsh, > 95% 
Deep marsh, > 50% 
Deep marsh, > 5% 
Deep marsh, dry 
Shallow marsh, > 95% 
Shallow marsh, >50% 
Shallow marsh, > 5% 
Shallow marsh, < 5% 
Shallow marsh, dry 
Wet meadow, wet 
Wet meadow, dry 
Low prairie, wet 
Low prairie, dry 
Tilled 

Totals 913 462 94 99 

'Total sample of 913 sloughs from the whole Alberta parkland. 

^These subsamples, totalling 655 of the 91 3 sloughs, represent each region ofthe Alberta parkland. The regions are considered 

natural but they were defined here by political (linear) boundaries. Consequently 258 sloughs are excluded from the regional 

subsamples but included in the total sample (see Figure 1). 

region) formed 6% of the smallest class and were Central region and become less common as size 
less common as size increased. Small shallow increases. Wet meadows and low prairies are the 
marshes are the commonest slough type in the commonest slough types in Southern Edge and 

Table 2 — Regional distribution of slough types in five size classes expressed as percentage of all sloughs in each region and 
total number of sloughs of each size by region. A— all sloughs, C— Central Parkland, SE— Southern Edge, WA— Willow- 
Aspen (see Figure 1). 

Low prairie Number 

Size Open Deep Shallow and of 

class Region pond marsh marsh wet meadow Tilled sloughs 

0.04-0.20 ha 
(0.1-0.5 ac) 

0.21-0.42 ha 
(0.6-1.0 ac) 

0.43-0.82 ha 
(1.1-2.0 ac) 

0.83-2.02 ha 
(2. 1-5.0 ac) 

> 2.2 ha 
(>5.0ac) 



A 


1.5 


4.5 


27.0 


18.9 


7.4 


543 


C 


1.5 


5.8 


33.3 


14.1 


6.7 


284 


SE 


2.1 


1.1 


3.2 


28.7 


24.5 


56 


WA 








15.2 


50.5 


3.0 


68 


A 


1.9 


3.9 


10.6 


4.3 


1.2 


200 


C 


1.1 


3.9 


12.8 


1.5 


1.3 


95 


SE 


1.1 





5.3 


17.0 


4.2 


26 


WA 


1.0 





5.0 


9.1 





15 


A 


1.2 


2.3 


3.7 


2.1 


< 1 


90 


C 


1.5 


3.0 


3.0 


1.7 


< 1 


47 


SE 








2.1 


6.4 


1.1 


9 


WA 


1.0 





7.1 


1.0 





9 


A 


1.4 


1.4 


2.3 


< 1 


< 1 


52 


C 


1.1 


1.7 


1.5 


< 1 





21 


SE 











1.1 


1.1 


2 


WA 








6.1 








6 


A 


<1 


1.2 


<1 








28 


C 


< 1 


1.3 


1.3 








15 


SE 








1.1 








1 


WA 


1.0 














1 



116 



The Canadian Field-Naturalist 



Vol. 92 



Willow-Aspen. They also become less common 
as size increases and are rare above 0.82 ha. 
Tilled sloughs were uncommon above the two 
smallest sizes (0.42 ha) and tilled sloughs were 
three times as frequent in the Southern Edge as 
anywhere else. 

The modal heterogeneity index (see Methods) 
of 1.0 for all regions in Table 3 means that only 
one vegetation type or land-use type was found 
on each transect through a slough (Figure 3). 
The percentage of index values > 2.0 is a 
measure of the commonness of slough borders 
having the equivalent of two vegetation types or 
one vegetation type and one land-use type on 
each transect. Alternatively, a value of 2.0 could 
mean three different vegetation types on each of 
two transects and one land use on each of two 
others. The Southern Edge has only 1% of 
sloughs above an index of 2.0 compared to 29% 
for the Willow-Aspen, 36% for the Central 
region, and 27% for all sloughs. 

Wolf Willow, Buckbrush, and roses form 
preferred nest sites for Mallards (Anas plat- 
yrhynchos) and are common nest sites for other 
species in the parkland (Smith 1971). For all 



sloughs studied and for Central parkland 
sloughs, these shrubs were found commonly 
within 50 m of sloughs only if the heterogeneity 
index was above 1.75. 

Table 4 shows that total heterogeneity 
exceeded agricultural heterogeneity in only a 
little over half of all sloughs. In other words, in 
nearly half the sloughs, agricultural crops 
accounted for all the heterogeneity indexed! 
This relationship is extreme in the Southern 
Edge where crops constituted all the hetero- 
geneity for over 94% of the sloughs. In the 
Central and Willow-Aspen regions over 30% of 
sloughs had heterogeneity due to vegetation 
other than agricultural crops. 

The difference between total heterogeneity 
and agricultural heterogenity was due to natural 
components (woody, clearings, other sloughs). 
This natural heterogeneity equalled or exceeded 
agricultural heterogeneity in over 30% of all 
sloughs studied except those in the Southern 
Edge. 

Where natural heterogeneity exceeded woody 
heterogeneity, the excess was due to natural 
clearings or neighboring sloughs. These natural 



Table 3 — Frequency distribution of mean heterogeneity index values' for all sloughs and for sloughs in each study region of 
Alberta 



Total 

heterogeneity 

index 



All 
sloughs 



Central 



Southern 
Edge 



Willow- 
Aspen 



1.00 

1.25 
1.33 
1.50 
1.67 
1.75 
2.00 
2.25 
2.33 
2.50 
2.67 
2.75 
3.00 
3.25 
3.33 
3.50 
3.67 
3.75 
4.00 
4.25 
4.33 



359 


147 


87 


28 


81 


50 





5 


24 


9 


3 


4 


55 


32 





6 


29 


13 


1 


6 


52 


17 





12 


63 


29 


2 


9 


46 


26 


1 


5 


22 


12 





6 


40 


28 





3 


20 


14 





1 


32 


22 





5 


44 


27 





5 


14 


9 





1 


6 


3 





2 


9 


9 








5 


5 








4 


4 








6 


4 





1 


1 


1 








1 


1 









Number of sloughs 



913 



462 



94 



99 



'Defined in Methods. 



1978 



Merriam: Sloughs and Aspen Parkland, Alberta 



117 



Table 4 — Regional comparison of heterogeneity of slough borders as shown by components of heterogeneity, absence 
of particular vegetation types, and the completeness of the ring of woody vegetation 

Percentage frequencies 



All 
sloughs 



Central 



Southern 
Edge 



Willow- 
Aspen 



Total heterogeneity' > agricultural heterogeneity 
Natural heterogeneity ^ agricultural heterogeneity 
Natural heterogeneity > woody heterogeneity 

Aspen and willow absent 
Shrub vegetation^ absent 
Aspen, willow, and shrub absent 

Woody border Class 1 (open)'' 

Class 2 (half closed) 
Class 3 (closed) 



56.6- 

34.1 

26.1 

43.8 
92.4 
48.1 

58.4 

8.8 

32.8 



64.9 


5.3 


40.3 


4.3 


34.5 


0.0 


43.3 


93.6 


90.3 


100.0 


43.3 


93.6 


53.3 


94.7 


6.9 


2.1 


39.8 


3.2 



68.7 
32.3 
19.2 

37.4 
90.9 
31.3 

40.4 
17.2 
37.4 



'Heterogeneity components defined in Methods. 

^No categories are mutually exclusive, percentages will not sum to 100 except for the three classes of woody border. 
^Wolf Willow and/or Buckbrush and/or roses and/or raspberries and/or Saskatoons. 

"The degree of completeness of the woody border around sloughs. Class 1 means a quarter ring or less of continuous border, 
class 2 means .25 to .75 of the perimeter is continuously bordered, class 3 means from .75 to a complete ring (see Methods). 



sources of heterogeneity were most frequent 
(34%) in the Central region, much less frequent 
(19%) in Willow-Aspen, and totally absent from 
the sample in the Southern Edge. Slough 
densities are lower there and natural clearings 
are no longer common. 

The percentage of sloughs that lacked aspen 
and willow was very high in the Southern Edge 
(93%, Table 4) and no sloughs in that region had 
the three shrub species. The combined absence 
of woody and "shrub" vegetation is much less 
common in the Willow-Aspen region because 
willow is so widespread. 

Woody border classes index the continuity of 
aspen and willow on the slough perimeter. 
Sloughs tend to be either open or closed except 
in the Willow-Aspen region where half-closed 
borders are more common (Table 4). In other 
regions and especially in the Southern Edge, 
open borders predominate. Smith (1971) show- 
ed that Mallards and Lesser Scaup (Athya 
affinis) preferred half-closed borders. Blue- 
winged Teal {Anas discors) preferred open, and 
American Wigeon {Mareca americana) pre- 
ferred closed. 

Forces Changing Slough Borders 

In 1 974 dead and dying aspen and willow were 
frequent components of slough borders because 
of two years of continuous inundation. Some 
plants leafed out again in 1974 but failed by July 



and were totally dead by August or September. 
Some had died in 1973 and already were 
dropping woody material into the sloughs. 

Dead willow was recorded 65 times on 
transects on 29 sloughs in 13 quarter sections 
mainly in the Central region. Dead aspen 
occurred 64 times on transects through 34 
sloughs on 13 quarters. In most cases, if water 
levels killed willow, aspen also was killed. 
Generally the killed aspen was in the two 
immature classes. But mature trees certainly 
were not immune. 

Clearing of aspens and/ or willows for 
agricultural purposes from 1970 to 1974 was 
observed on 17 of 74 quarter sections (23%). Of 
the 17, 8 had extensive clearing, 8 had Httle 
clearing, and only 1 had moderate clearing. Six 
of the 8 with extensive clearing also were subject 
to very intensive agriculture. The 8 with little 
clearing showed no clear relationship with 
agricultural intensity. These results suggest that 
extensive clearing often is associated with 
intensive agriculture. It also seems that clearing 
usually was either extensive or minor and 
seldom moderate. Discussions with farmers 
indicated that amount of clearing depends more 
on availability of capital than on land-use 
considerations. Marginal farming operations 
can fund aspen clearing with heavy equipment 
less frequently and to lesser extents. Extensive 
clearing, however, does occur on marginal lands. 



118 



The Canadian Field-Naturalist 



Vol. 92 



very often with no agricultural follow-up and 
consequent aspen regrowth. 

"Developments" other than agriculture were 
not frequent individually but together they 
affected 14 of the 74 quarter sections sampled. 
Usually these were not the same quarters subject 
to intense agriculture so that these "develop- 
ments" additively increase the potential impact 
on wildlife habitat. The number of quarters on 
which various developments occurred were 
ditching and dugout ponds, 3; gas lines, wells 
and flares, 3; gravel pits, 1 ; housing, 3; municipal 
dump, 1; oil rigs and wells, 1; power lines, 2. 

Only one successful removal of a slough by 
drainage was noted but water levels were so high 
in 1974 that much slough drainage in the 
parkland was not observable. Filling of sloughs 
with soil for agricultural purposes was noted 
only once. Filling with trash, car bodies, etc. is 
all too common. Although death or damage to 
woody vegetation by herbicide was observed 
frequently away from sloughs, records do not 
indicate that use of herbicide was a major 
controller of woody vegetation around sloughs. 
This does not reduce the possibility that 
herbicides may enter sloughs and significantly 
affect them in other ways. 

In addition to these particular forces slough 
borders are shaped by the major, but poorly- 
defined forces of successional maturation. 

Changes in Slough Borders 1945-1949 to 1974 
Table 5 summarizes changes in the woody 
vegetation types for a subsample of sloughs 
studied in the field in 1974 and for which 
airphotos taken between 1945 and 1949 were 
available. Measurements of changes in vege- 



tation during the 25- to 29-year interval are 
described in Methods. 

Immature aspen decreased around 85% of the 
sloughs and mature aspen decreased around 
59% of them. PO I/II decreased around 250 
sloughs but lessthanhalf of those changes can be 
explained by aspen maturation because only 102 
sloughs had an increase in PO III/ IV. The 
sloughs with no change are approximately 
balanced between PO I/II and PO III/ IV and 
can be assumed to indicate stable replacement in 
those few cases. If 102 of the decreases in PO I/II 
are explained by the number of increases in PO 
III/ IV, then a minimum of 148 decreases in PO 
I/II are not explained by maturation. A 
maximum of 30 of the 183 decreases in PO 
III/ IV could be cancelled by the 30 increases in 
PO I/II. These remaining decreases in both 
maturity classes are not explainable by matura- 
tion and indicate a lack of stable replacement. 
This also is shown by the mean net losses per 
slough of 32% of young aspen and 9% of older 
aspen. The mean net losses of the two aspen 
classes underestimates the importance of aspen 
losses from around many sloughs spread widely 
through the study area and overestimates losses 
for a few areas in the central parkland with large 
numbers of sloughs and large net gains in aspen. 

Willows increased around 22% of the sloughs 
(Table 5) in those quarter sections where water 
levels and land management permitted, but 
willows decreased much more than they gained. 
Of the 209 decreases in Table 5, only 29 were 
caused by high water in 1972-1974; apparently 
losses have continued for a long time. Even over 
a quarter century, a mean net loss of 0.22 ha 
(0.66 acres) or 68% of the willow area around 



Table 5— Changes in area of major vegetation types within 50 m of 398 sloughs from 1945-1949 to 1974 



POI/II' POIII/IV' 



Willow^ 



Shrub-^ 



No. sloughs with increase 

No. sloughs with no change'' 

No. sloughs with decrease 

x hectares per slough 1945-19495 

"x hectares net change per slough 

X % loss of area per slough 



30 
16 
250 
1.53 
-0.48 
32 



102 

23 

183 

1.78 
-0.16 
9 



61 
10 
209 
0.32 
-0.22 



17 

5 
161 

0.23 
-0.17 
74 



iPO I — aspen saplings or suckers, PO II — growing immature aspen, PO III — prime mature aspen, PO IV — overmature 
aspen (see Methods for definitions). 
-Willow (Sali.x spp.). 
^As defined in Table 4. 

■♦Sloughs were excluded from consideration if the vegetation type was absent in both 1945-1949 and 1974. 
'Variable sample size (See •"). 



1978 



Merriam: Sloughs and Aspen Parkland, Alberta 



119 



Table 6 — Changes from 1945-1949 to 1974 in total area of 
all major woody vegetation in borders of 398 sloughs in 35 
quarter sections' 





Quarter sections 


Sloughs 


No. with no net change 


2 


15 


No. with net increase 


3 


62 


No. with net decrease 


30 


321 


T net change (ha) 


-11.7 


-1.0 


rioss(% 1945-1949 area) 


55.7 


55.7 



'Complete data available from Canadian Wildlife Service, 
Western Region, Edmonton, or from the author. 

each slough, is a striking reduction. 

"Shrub" vegetation decreased in area around 
90% of sloughs and increased around only 9% of 
them. The average loss of 0.17 ha (0.43 acres) or 
74% of the 1945-1949 shrub area within 50 m of 
these sloughs is another massive habitat change. 

Table 6 summarizes the changes shown in 
Table 5 by quarter sections and by sloughs with 
no distinction of border vegetation types. There 
was a net decrease in woody vegetation within 
50 m of sloughs in 86% of the quarter sections 
while only 9% had an increase. Vegetation types 
recorded here decreased on 80% of the sloughs 
and increased on only 15% which are located 
mainly on a small number of quarter sections 
with high densities of sloughs in the Central 
region. The net loss of four major vegetation 
types around 398 sloughs amounted to 413 ha 
(1020 acres) over about three decades. 

Records of total removal of woody borders by 
1974 from sloughs which had woody borders in 
1945-1949 give another view of clearing. Woody 
borders were totally eliminated from 126 out of 
398 sloughs compared (on 21 of 35 quarter 
sections). Three of the 35 quarters lost all woody 
borders from over 75% of woody-bordered 
sloughs, 8 lost all woody borders from 50 to 75%, 
and 5 lost them from 25 to 50%. Only 8 sloughs 
gained new woody borders between 1945-1949 
and 1974 and most of those were simple willow 
rings. 

A minimum estimate of the dynamics of 
woody vegetation within 50 m of slough margins 
during this period of 25 to 29 years can be given 
by adding total decreases in area to total 
increases in area for each of the four vegetation 
classes. These are minimum rates of turnover 
because compensatory changes at the same 



slough cannot be measured. Turnover for 
immature aspen was 221 ha compared to 240 ha 
present in 1945-1949. For mature aspen it was 
224 ha compared to 277 ha, for willows 124 ha 
compared to 124 ha, and for shrubs it was 86 ha 
compared to 93 ha present in 1945 1949. Thus, 
the minimum total turnover of the four 
vegetation types around these 396 sloughs was 
655 ha compared to 734 ha present in 1945- 
1949. 

Discussion 

Alberta's aspen parkland needs to be treated 
regionally in considering environmental rela- 
tionships or management interventions. Moss 
(1932) divided the parkland into a northern 
"poplar area," with coniferous associates, and a 
southern "parkland" of aspen groves and 
grassland parks. Others have separated a willow- 
aspen region along the foothills south of the 
Bow River, an aspen-poplar region northeast 
from there, and an aspen ecotone northwest 
from the Bow to the boreal forest (Alberta 
Government 1969). The parkland regions that I 
used for data analysis show differences both in 
the sloughs and in the habitats bordering them. 
Division of Alberta parkland into Willow- 
Aspen, Southern Edge, and Central regions is 
prehminary and the natural boundaries are 
undefined but these regions were meaningful in 
this study. 

Heterogeneity of habitats bordering sloughs 
in all three regions, and in the total sample, had a 
modal index value of 1.0 (Table 3). This value 
indicates a norm of only one vegetation or land- 
use type on any side of the slough. Index values 
> 2.0 were as common in the Willow-Aspen and 
Central as they were in the total sample. 
Southern Edge had significantly fewer index 
values > 2.0 indicating that the chance of finding 
two different vegetation or land-use types on 
every side of a slough was rare in the Southern 
Edge. 

Separation of the basic heterogeneity index 
into some of its major components reveals the 
origins of heterogeneity in the slough margins. 
Agricultural components contributed the total 
heterogeneity around 94% of sloughs in the 
Southern Edge compared to about 30% in all 
other regions. Agriculture can add important 
components to the heterogeneity of slough- 



120 



The Canadian Field-Naturalist 



Vol. 92 



centered habitat mosaics, but clearly agriculture 
also can severely reduce the total heterogeneity 
of the mosaic. Because differences in land use 
follow ownership boundaries, the minimum area 
affected often is a quarter section. Woody 
vegetation might be expected to control hetero- 
geneity of slough borders in the Central 
parkland but it does not. Few quarter sections 
are completely colonized by woody vegetation 
and these are balanced by a few with no 
remaining slough borders. Most quarters have 
slough borders narrower than 50 m and so the 
transects crossed them and recorded agricultural 
land use as a major component of total 
heterogeneity. 

The contribution of natural habitats to total 
heterogeneity equals or exceeds the agricultural 
component in about one third of all sloughs. 
Natural habitats in the Central parkland are 
dominated by aspen and willow but frequently 
also included other sloughs and some natural 
clearing. In the Willow-Aspen parkland, natural 
habitats were mainly willow. 

The "shrub" group was not included in the 
"woody" vegetation as discussed here but was an 
important component of natural heterogeneity. 
These shrubs which are important habitats for 
many species, including ducks, were not record- 
ed for over 90% of sloughs even in the Central 
parkland. "Shrubs" were common within 50 m 
of sloughs only when the heterogeneity index 
was above 1.75. 

The transect index of heterogeneity that was 
used here efficiently yielded meaningful quanti- 
tative data. This data base can be compared 
against future surveys to measure changes in the 
structure of habitat mosaics around sloughs. 
The same approach should be useful in many 
other situations both on the ground and from 
airphotos. 

Both the theoretical and applied ecological 
literature supports the contention that hetero- 
geneity can be related to faunal richness 
(Telfer 1974; MacArthur 1972; Elton 1966; 
Levins 1962). The losses of vegetation types 
recorded over the last quarter century imply that 
heterogeneity around sloughs is decreasing. If 
faunal richness is valued, these reductions in 
heterogeneity deserve attention in both manage- 
ment and research. 

Changes in amount of four classes of woody 



vegetation during 25 to 29 years were measured 
around 398 of the total 913 sloughs studied. 
Although encroachment of woody vegetation 
into grassland clearings in the aspen parkland 
has received much attention (see, for example, 
Bailey and Wroe 1974; Johnston and Smoliak 
1968; Moss and Campbell 1947), the net changes 
in woody vegetation recorded here, mainly from 
farming regions, are all losses. All four 
vegetation classes lost area from within 50 m of 
sloughs. Compared to the 1945-1949 areas, the 
1974 areas were reduced by 32% for immature 
aspen, 9% for mature aspen, 68% for willow, and 
74% for shrubs. Each vegetation type was 
reduced around the majority of sloughs, but all 
vegetation types were not reduced around every 
slough. During about three decades of this 
country's rapid technological change following 
World War II, about 408 ha of four major 
vegetation types disappeared from within 50 m 
of all the sloughs in 35 quarter sections of 
Alberta parkland. Average losses from each 
slough included nearly half a hectare of 
immature aspen, one third as much mature 
aspen, nearly a quarter hectare of willows, and 
almost as much upland "shrubs." Woody 
borders were lost completely from 32% of these 
sloughs while only 2% added new woody 
borders. 

Agricultural land management is a major 
cause of these changes. Clearing of woody 
vegetation, mainly by hand, was becoming 
common around sloughs in the 1945-1949 
airphotos. Clearing has continued with increas- 
ing technological aid from then until the end of 
the study. In 1974 extensive clearing was 
associated with intensive agriculture both on 
particular farms and in intensively farmed 
regions such as the Southern Edge of the 
parkland. Cultivation practices also have been 
important in changing these habitats. Repeated 
cultivation is necessary to prevent revegetation 
of cleared land, especially by aspen suckers. 
Cultivation right to the edge of sloughs and 
tillage of the entire slough basin are clearly 
important to slough habitats. It is not clear that 
these practices always produce substantial 
economic benefits for agriculture (see also, 
Lodge 1969). There are many examples, par- 
ticularly in the Central parkland, of beef, grain, 
and cash-crop farming without major reductions 



1978 



Merriam: Sloughs and Aspen Parkland, Alberta 



!21 



of slough borders. 

Both natural and human forces will interact to 
determine the future of parkland sloughs and 
their bordering habitats. Merriam (1975. Aspen 
parkland slough habitats in Alberta. Un- 
published report, Canadian Wildlife Service, 
Edmonton, Alberta, 68 pp.) discusses these 
influences in relation to management. In fact 
some of the present qualities of sloughs which we 
value may have resulted from human inter- 
vention. For example, some small deep marshes 
and shallow marshes which were studied in 1974 
were almost totally shaded by overhanging 
aspen canopies in 1947. Early stages of hand- 
clearing were seen on 1947 airphotos. By 1974 no 
aspen borders remained on these sloughs but the 
plant and waterfowl productivity of the sloughs 
themselves was high, probably much higher than 
under those early aspen canopies. It also was 
evident in the field in 1974, however, that these 
and many other sloughs without woody borders 
were filling both with their own production of 
organic matter and with eroded soil. Clearing 
and cultivation of slough borders may have 
given many parkland sloughs a substantial boost 
in productivity which could drastically shorten 
their lifespan by accelerating filling. 

Bird ( 1 96 1 ) in a historical review of land use in 
Canada's parkland noted that introduction of 
the bulldozer into parkland agriculture in 
1945-1948 was a signal event. Between 1946 and 
1952 in Manitoba parkland alone Bird reported 
that from 120 000 to 170 000 ha were cleared 
and broken. More than agricultural production 
had to be affected by new technological inter- 
ventions in the dynamics of parkland vege- 
tation. Smith (1971) noted that "The greatest 
change in the Lousana environment (near 
Elnora, Alberta) resulted from the cutting of 
trees and the plowing and planting of individual 
pond basins . . .". Smith's data show that in 1953 
on his study area, about 50% of sloughs had 
complete woody borders, 18% were half- 
bordered, and 32% were unbordered. By 1969 
these figures reversed and became 28% com- 
pletely bordered, 18% half-bordered, and 54% 
unbordered. Kiel et al. (1972) reported that for 
their Manitoba study area, clearing of woody 
slough borders increased greatly after 1954. 
They found that land-clearing altered more 
sloughs in the period 1961-1964 than in the 



previous 12 years (1949-1960). From 1949 to 
1964 they found that 37% of 120 sloughs were 
altered by land-clearing. These 44 sloughs were 
affected 57 times by clearing operations. 

My results show that heterogeneity of habitats 
bordering sloughs also is strongly influenced by 
agriculture. For example, in the Southern Edge 
more than 94% of slough borders derived their 
heterogeneity entirely from agricultural crops 
(Table 4). If the Willow-Aspen region were not 
used primarily as rangeland, it is unlikely that 
woody vegetation and natural features could 
control the heterogeneity of nearly 70% of the 
slough borders (Table 4). The strength of 
agricultural forces in the Central region is 
evident from differences among slough borders 
in Figure 1 as well as from the data. It seems clear 
that although habitat changes are functions of 
natural phenomena, they also are directed by 
socio-economic forces. 

Goodman and Pryor (undated. A preUminary 
study of alteration of waterfowl habitat in the 
black soil zone of western Canada. Unpublished 
report, Canadian Wildlife Service, Edmonton, 
Alberta, 55 pp.) concluded that for Canada's 
parkland the net loss of water-surface area of 
sloughs by 1970 was between 14% and 23% of the 
pristine surface area. Net losses of entire sloughs 
by 1970 were between 6% and 10% of the 
pristine number of sloughs. My results show 
that changes in habitats around sloughs in 
Alberta's parkland were more extensive than 
could be inferred from the changes that 
Goodman and Pryor reported for the sloughs 
themselves. The average loss of the four major 
vegetation types studied was just over 1 ha per 
slough or 11.7 ha per quarter section during a 
quarter century. At the same time 33% of the 
sloughs studied lost their woody borders 
completely. 

When woody slough borders are lost, most 
other woody parkland habitats have already 
disappeared. The extensive habitat changes 
reported here for slough borders and the 
reduction of heterogeneity by application of 
agricultural practices to whole quarter sections 
have changed the basic structure of Alberta 
parkland. The natural mosaic of grassland, 
woody habitats, and sloughs is becoming a 
coarser mosaic of more homogeneous quarter 
sections. 



122 



The Canadian Field-Naturalist 



Vol. 92 



Acknowledgments 

Jim Patterson interested me in the aspen 
parkland and facilitated the study in many ways. 
Aileen Merriam shared the field work equally 
and provided botanical expertise. Len Shand- 
ruck, Ed Telfer, Gordon Miller, Alex Johnston, 
Art Bailey, and Jack Miller all were generous 
with their time and knowledge. Criticisms of 
manuscripts by Al Barlow, David Munro, and 
especially by George La Roi were very helpful. 
John Wegner gave critical assistance in final 
analyses and manuscript preparation. The study 
was financed by the Canadian Wildlife Service, 
Western Region and by Carleton University. 

Literature Cited 

Alberta Government. 1969. Atlas of Alberta. Government 

of Alberta and the University of Alberta, University of 

Toronto Press, Toronto. 158 pp. 
Bailey, A. W. and R. A. Wroe. 1974. Aspen invasion in a 

portion of the Alberta parklands. Journal of Range 

Management 27(4): 263-266. 
Bird, R. D. 1930. Biotic communities of the aspen park- 
land. Ecology 11: 356-442. 
Bird, R. D. 1961. Ecology of the aspen parkland of 

western Canada in relation to land use. Contribution 27, 

Research Station, Canada Department of Agriculture, 

Winnipeg, Research Branch, Canada Department of 

Agriculture, Ottawa. 155 pp. 
Bird, C. D. and R. D. Bird. 1967. The aspen parkland. 

In Alberta, A natural history. Edited by W. G. Hardy. 

Hurtig Publishers, Edmonton, pp. 135-150. 
Brayshaw, T. C. 1965. Native poplars of southern Alberta 

and their hybrids. Canada Department of Forestry 

Publication 1 109. 40 pp. + map. 
Coupland, R. T. 1950. Ecology of mixed prairie in Canada. 

Ecological Monographs 20: 271-315. 
Elton, C. S. 1966. The pattern of animal communities. 

Methuen, London. 432 pp. 
Hansen, H. P. 1949. Postglacial forests in south central 

Alberta, Canada. American Journal of Botany 36: 

54-65. 
Horton, K. VV.and J. S. Maini. 1964. Aspen reproduction, 

its characteristics and control. Canada Department of 

Forestry Monograph, Project 0-2, Richmond Hill, 

Ontario. 85 pp. 
Johnston, A. and S. Smoliak. 1968. Reclaiming brushland 



in southwestern Alberta. Journal of Range Management 
21(6): 404-406. 

Kiel, W.H., Jr., A. S. Hawkins, and N. G. Ferret. 1972. 
Waterfowl habitat trends in the aspen parkland of 
Manitoba. Canadian Wildlife Service Report Series 
Number 18. 63 pp. 

Levins, R. 1962. The theory of fitness in a heterogeneous 
environment. I. The fitness set and adaptive function. 
American Naturalist 96: 361-378. 

Lodge, R. W. 1969. Agricultural use of wetlands. In 
Saskatoon Wetlands Seminar. Canadian Wildlife Service 
Report Number 6. pp. 1 1-15. 

MacArthur, R. L. 1972. Geographical ecology. Harper and 
Row, New York. 269 pp. 

Maini, J. S. 1960. Invasion of grassland by Populus 
tremuloides in the northern great plains. Ph.D. thesis, 
University of Saskatchewan, Saskatoon. 231 pp. 

Moss, E. H. 1932. The vegetation of Alberta. IV. The 
poplar association and related vegetation of central 
Alberta. Journal of Ecology 20: 380-415. 

Moss, E. H. 1959. Flora of Alberta. University of Toronto 
Press, Toronto. 546 pp. 

Moss, E. H. and J. A. Campbell. 1947. The fescue grass- 
land of Alberta. Canadian Journal of Research C 25: 
209-227. 

Roe, F. G. 1939. Buffalo as a possible influence in the 
development of prairie lands. Canadian Historical Review 
20: 275-287. 

Smith, A. G. 1971. Ecological factors affecting waterfowl 
production in the Alberta parklands. United States 
Department of the Interior, Fish and Wildlife Service, 
Bureau of Sport Fisheries and Wildlife, Resource 
Publication 98. 49 pp. 

Stewart, R. E. and H. A. Kantrud. 1969. Proposed classi- 
fication of potholes in the glaciated prairie region. In 
Saskatoon Wetlands Seminar. Canadian Wildlife Service, 
Report Number 6. pp. 57-69. 

Stewart, R. E. and H. A. Kantrud. 1971. Classification of 
natural ponds and lakes in the glaciated prairie region. 
Resource Publication U.S. Bureau of Sport Fisheries and 
Wildlife. 26 pp. 

Stoudt, J. H. 1971. Ecological factors affecting waterfowl 
production in the Saskatchewan parklands. United States 
Department of the Interior, Fish and Wildhfe Service, 
Bureau of Sport Fisheries and Wildlife, Resource Publi- 
cation 99. 58 pp. 

Telfer, E. S. 1974. Logging as a factor in wildlife ecology in 
the boreal forest. Forestry Chronicle 50: 1-5. 

Received 26 September 1975 
Accepted 10 February 1978 



Decline of a Ruffed Grouse Population in Manitoba 



Donald H. Rusch,' Murray M. Gillespie, and David I. McKay 

Research Branch, Department of Renewable Resources and Transportation Services, Winnipeg, Manitoba R3H 0W9 
'Present address: Wisconsin Cooperative Wildlife Research Unit, University of Wisconsin, Madison, Wisconsin 53706. 

Rusch, Donald H.. Murray M. Gillespie, and David I. McKay. 1978. Decline of a Ruffed Grouse population in Manitoba. 
Canadian Field-Naturalist 92(2): 123-127. 

Estimated numbers of adult Ruffed Grouse (Bonasa umbellus) on a 1 195-ha portion of the Narcisse Wildlife Management 
Area near Chatfield, Manitoba, declined from 309 in June 1971 to 132 in November 1971; then to 43 in June 1972, and 
eventually to 18 in April 1973. Numbers of drumming males were 100, 3, and 4 in the springs of 1971, 1972, and 1973, 
respectively. A major decline in numbers of Snowshoe Hares (Lepus americanus) coincided with the decrease in grouse 
populations. Production of young grouse was excellent in both 1971 and 1972. Survival rates of young and adult grouse were 
not unusually dissimilar, but both were extremely low. Many Ruffed Grouse lost during summer 1971 were consumed by 
predators, and field evidence suggested that most of these were killed by the predators. We suggest that the 197 1 -1 972 decline 
in numbers of Ruffed Grouse in central Manitoba may have been due to increased mortality of young and adults that resulted 
from a shift in diets of predators from Snowshoe Hares to Ruffed Grouse during a decline in the population of hares. 

Key Words: Ruffed Grouse, populations, cycles, predation, Manitoba. 



This paper documents the 1971-1972 decline 
in populations of Ruffed Grouse {Bonasa um- 
bellus) populations in the Interlake Region of 
Manitoba. It describes major demographic 
changes accompanying the decline, and also an 
association between numbers of grouse, num- 
bers of Snowshoe Hares {Lepus americanus), 
and diets of certain raptors. 

Dramatic and periodic fluctuations in num- 
bers of grouse and hares were noted by early 
naturalists in Manitoba (Griddle 1930: Seton 
1929, pp. 705-710). Keith (1963) assembled 
and summarized the evidence for a 10-year cycle 
of several wildlife species and concluded, in part, 
that grouse had fluctuated cyclically in Mani- 
toba. This conclusion was derived mainly from 
provincial estimates of grouse harvests, and 
Keith noted the paucity of estimates of grouse 
numbers during cyclic declines. Ransom (1965) 
documented a decline in numbers of Ruffed 
Grouse in Manitoba's Turtle Mountains during 
1961-1963. He concluded that the decline was 
not wholly due to reproductive failure, but did 
not speculate on other possible causes. Gullion 
(1970b) recorded a decline (approximately 65%) 
in Ruffed Grouse populations at Cloquet. 
Minnesota in 1961-1964. He associated portions 
of the decline with unusually heavy losses to 
predation in 1961 (Eng and Gullion 1962; 
Gullion 1970a, p. 110) and again in 1963-1964 
(Gullion 1970b, p. 95), but stressed the overall 
importance of winter weather, food supplies, 
and the condition-reproduction-recruitment 
relationship in limiting the abundance of Ruffed 
Grouse. 



Study Area and Methods 

Most of our field work from April 1971 to 
April 1973 was conducted on a 1 195-ha portion 
of the Narcisse Wildlife Management Area, 
1.8 km south of Chatfield, Manitoba (50°47'N, 
97°34'W). Approximately 60% of the study plot 
was covered by upland forest. Other cover types 
were old fields (14%), burn (19%), and marsh 
(7%). The overstory of the upland forest was 
dominated by 20- to 30-year-old aspen {Populus 
tremuloides). The most common shrubs of the 
intermediate understory were Saskatoon {Ame- 
lanchier alnifolia), willow {Salix spp.), hazel 
{Cory/us cornuta), and red-osier dogwood 
{Cornus stolonifera). The most common shrubs 
in the ground layer were rose {Rosa spp.) and 
snowberry {Symphoricarpos occidentalis). Den- 
sities of woody plants were estimated from 25 
quarter-method (Cottam and Curtis 1956) 
samples with modified calculations (Rusch and 
Keith 1971a). 

Counts of drumming males (Gullion 1966) 
were conducted on the Narcisse study plot in 
April and May 1971-1973. In spring and other 
seasons, numbers of Ruffed Grouse were esti- 
mated on transects by the King strip method 
(Leopold 1933, p. 152: Rusch and Keith 1971b). 
Numbers of hares tallied along these transects 
were used as indices to hare populations. 
Although all habitats on the study plot were 
searched and traversed, all drumming logs. 
Ruffed Grouse and hares were observed in or 
within 100 m of upland forests. 

The nests of large raptors were located from 
aircraft in April 1971. Nests were checked for 



123 



124 



The Canadian Field-Naturalist 



Vol. 92 



raptor activity from the ground in May and June 

1971 and 1972, and pellets and food remains 
were subsequently collected from active nests. 

Numbers and ages of grouse in bags of hunters 
were obtained from check stations established at 
Gunton and Woodlands, Manitoba. These 
grouse were taken from the area between Lakes 
Winnipeg and Manitoba on the east and west 
and between the cities of Winnipeg and Grand 
Rapids on the south and north. In 1970 and 
1971, bags were checked on the first two days of 
the grouse season, Fridays and Saturdays. In 

1972 and 1973, bags were checked on the first 
two Saturdays of the grouse season. 

Indices to the numbers of Ruffed Grouse 
harvested by hunters in 1971-1973 were ob- 
tained from unpublished data generously pro- 
vided by the Manitoba Department of Renew- 
able Resources and Transportation Services, the 
Minnesota Department of Natural Resources 
(W. H. Longley, personal communication), and 
the Wisconsin Department of Natural Re- 
sources (D.R. Thompson, personal communica- 
tion). 

Results 

Because our research did not begin until April 
1971, the precise time at which the decline in 
grouse numbers at Narcisse began is unknown. 
Numbers of drumming males on the Narcisse 
plot declined from 100 in 1971 to 3 in 1972 and 4 
in 1973; estimates of numbers of adult (>12 
months of age) and young (3-12 months of age) 
grouse in the spring declined from 309 in 1971 to 
43 in 1972 and 18 in 1973 (Table 1). Indices to 
grouse numbers declined sharply during the 



summer of 1971 (Table 1); between June and 
September 1971, estimated numbers declined by 
80% (from 1 600 to 3 1 7). at a rate of 1 .5 per day 
per 100 ha. The decline continued at a decreasing 
rate throughout the fall of 1971 and winter of 
1971-1972 and during all of the following year. 
Estimates of Ruffed Grouse numbers obtained 
in 1974 and 1975 suggest that populations had 
stabilized at low levels by the spring of 1973 (D. 
Caswell, personal communication). In both 
1971-1972 and 1972-1973, rates of decline were 
highest in summer and fall. 

Data obtained from bag checks of hunters in 
the Interlake area of Manitoba provide corro- 
boration of the severe decline in numbers of 
Ruffed Grouse (Table 2), as birds per hunter 
decreased from 1 . 1- in 1 970 to 0.8 in 1 97 1 and 0. 1 
in both 1972 and 1973. The estimates of Ruffed 
Grouse harvests in Manitoba ( 1 50 000, 1 70 000, 
50 000, and 36 000 in 1970-1973, respectively) 
provided additional evidence of a major decline 
(Figure 1). The Narcisse indices, bag check data, 
and hunter questionnaire data imply initiation 
of the decline in winter 1970-1971 or spring- 
summer 1971. 

A total of 70 drumming males was banded in 
the three springs (67 in 1971, 2 in 1972, and 1 in 
1973). Four of these were subsequently shot and 
reported by hunters, all within 400 m of 
respective banding sites. Eight of 46 grouse less 
than 6 months of age when banded in the fall (43 
in 1971 and 3 in 1972) were also shot and 
reported by hunters, all within 3.5 km of the 
banding sites. The mean capture-recovery dis- 
tance for these eight birds was 1.2 ±0.5 km. 
Nine of the 12 recoveries occurred on the study 



Table I — Indices (± SE) to numbers of Ruffed Grouse and Snowshoe Hares (numbers observed in parentheses) from 
periodic observations along transects on the 1 195-ha Narcisse study plot 



Date 



Transect 
length (km) 



Numbers of 
grouse' 



Grouse per 
100 ha' 



Hares per 
100 km 



23 June 1971 
3 Sept. 1971 
10 Nov. 1971 
22 June 1972 
13 Oct. 1972 
28 Dec. 1972 
26 April 1973 



182 


1600±178 (156)- 


1 34± 1 5 


155114(282) 


182 


317± 28 (44) 


27± 2 


23± 4 (42) 


195 


I32± 7 (24) . 


11± ! 


23± 4 (45) 


182 


184± 65 (18)' 


4± 3 


9± 2 (16) 


107 


43± 31 (6) 


3± 1 


8± 3 (9) 


161 


24± 2 (8) 


2± 1 


5± 2 (8) 


182 


18± 7 (4) 


2± 1 


2± 1 (4) 



'Estimates calculated by King formula (Leopold 1933. p. 152) appK to all Ruffed Grouse present on the stud\ plot. In.Iune 
1971 and 1972 juveniles were distinguished from adults and \oung b\ si/c. In other months, age of grouse could not be 
determined. 

-Estimate includes 1291 juveniles and 309 adults. 

'Estimate includes 141 juveniles and 43 adults. 



1978 



RUSCH ET AL.: RUFFED GROUSE, MANITOBA 



125 



Table 2— Percentage of young Ruffed Grouse in bags of hunters checked near Gunton and Woodlands, Manitoba 



Dates 



Numbers of 
hunters checked 



September 18, 19, 1970 
September 24, 25, 1971 
September 23, 30, 1972 
September 22, 29, 1973 



749 
1110 
1097 

397 



Number of Ruffed 
Grouse bagged 



895 
117 

38 



Percentage of 



young grouse 



62 
66 
66 

76 



plot. These movement data provide no evidence 
that egress from the study plot was excessive or 
that it exceeded ingress. But sample sizes are 
small, distribution of hunters is unknown, and 
the possibility of different rates of egress in 
different years cannot be ruled out. 

Ratios of juveniles (<3 months of age) to 
adults among birds flushed on the study plot in 
June 1971 and 1972 were similar(3. 3:1 and 3.5:1; 
chi-square = 0.006, P = 0.96). Percentages of 
young among Ruffed Grouse in bags of hunters 
at nearby check stations were identical (66%) in 
1971 and 1972 (Table 2). This is essentially the 
same as the weighted and unweighted 10-year 
mean percentages of young in hunter bags (64% 
and 65%, respectively, of 3922 grouse). 

Of the three drumming males present on the 



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Q 



< 

CO 

Z) 

o 

X 



CO 
LU 
> 

< 

X 

UJ 
CO 

Z) 

o 

CL 
(D 

Q 
UJ 



Z) 



MINNESOTA 




\^WISCONSIN 



MANITOBA 



1970 1971 1972 1973 



YEAR 

Figure 1. Indices to numbers of Ruffed Grouse harvested 
by hunters in Manitoba, Minnesota, and Wisconsin 
in 1971-1973. 



Narcisse plot in 1972, only one was a survivor of 
the 100 drumming in the previous spring; the 
other two were young birds. Lack of data on the 
sex and age structure of spring populations 
precludes calculation of precise survival rates for 
other population cohorts. Maximum survival 
rates, calculated from population estimates of 
grouse in June of 1971 and 1972 and assuming 
that all 43 adult grouse present in June 1972 were 
either one year of age or older (Table 1), were 
0.03 for young (43 of 1291) and 0.14 for adults 
(43 of 309). 

A crew of seven men intensively searched a 40- 
ha area of upland forest in late June 1971. No 
intact carcasses of grouse were found, but 
remains of 14 Ruffed Grouse were located. Field 
evidence (Rusch and Keith 197 la) suggested that 
10 of these were young that had been consumed 
by raptors within the previous 30 days. The 40- 
ha area was arbitrarily chosen because of access, 
but did not harbor a raptor nest or an unusually 
high number of drumming males (5 in 1971). 

Several species of raptors hunted on the 
Narcisse area, and some nests of larger raptors 
were found. Three pairs of nesting Great Horned 
Owls {Bubo virginianus) were located on or 
within 400 m of the Narcisse study plot in both 
1971 and 1972 and four pairs of nesting Red- 
tailed Hawks {Buteo jamaicensis) were found in 
each of these years. At least two pairs of Marsh 
Hawks {Circus cyaneus) utilized the area, but 
only one nest was found (on 29 June 1971). 
Raptor nests were not checked in 1973. 

Grouse and hares were identified and counted 
in pellets and remains collected in and near these 
raptor nests (Errington et al. 1940; Rusch et al. 
1972). A minimum of 29 Snowshoe Hares and 1 
Ruffed Grouse were identified in 31 owl pellets 
collected in May 1971. In June and July 1971, a 
minimum of 61 Snowshoe Hares and 68 grouse 
were identified in pellets and remains at nests of 
Red-tailed and Marsh Hawks. In May 1972, 



126 



The Canadian Field-Naturalist 



Vol. 92 



parts of one hare and three grouse were found in 
26 owl pellets. In June and July 1972, two hares 
and four grouse were identified among pellets 
and remains at Red-tailed Hawk nests. The ratio 
of grouse to hares in raptor diets thus changed 
from 0.03:1 in spring of 1971 to 1.1:1 in summer 
of 1971 (chi-square = 24.2, P^ 0.005). The latter 
ratio was not significantly different from the 
2.3:1 ratio observed in spring and summer of 
1972 (chi-square = 1.1, P = 0.31). 

We lack data to estimate densities of Snow- 
shoe Hares, but two independent indices 
suggested a severe decline in numbers of hares 
from 1971 to 1973. In 1971, 52 hares were 
captured in mirror traps during 1 74 trap days. In 
1972 and 1973, no hares were captured in mirror 
traps in 19 and 11 trap days, respectively (chi- 
square = 12.0, P ^ 0.005). On grouse-census 
transects, the number of hares seen per 100 km 
declined from 1 55 in June 1971 to 9 in June 1 972 
and to 2 in April 1973 (Table 1). 

Discussion 

Harvests of Ruffed Grouse in Manitoba, 
estimated from questionnaire data, indicate that 
the decline of Ruffed Grouse populations was 
probably province-wide and harvest estimates 
from Minnesota and Wisconsin showed similar 
trends (Figure 1). On the other hand, estimates 
of harvest by resident hunters in Ontario 
suggested no significant change in 1970-1973 
(L.R. Pim and R.M. Mitchell 1975, unpublished 
report. Ministry of Natural Resources. Queen's 
Park, Toronto, Ontario). In the past, harvests of 
Ruffed Grouse in Ontario, the Prairie Provinces, 
and the Lake States have followed generally 
similar trends (Keith 1963). 

To our knowledge, the decline in Ruffed 
Grouse numbers documented at Narcisse in 
1971-1973 is the most severe ever recorded. 
Rates of decline were highest in summer 1971 
and progressively lower thereafter. Fall ratios of 
young to adult grouse did not change significant- 
ly during the decline, implying that reproductive 
failure was not an important contributing factor. 
Ransom (1965) reached a similar conclusion on 
the basis of his observations of a 1961 decline of 
Ruffed Grouse in the Turtle Mountains. Sur- 
vival rates of both young and aduh grouse at 
Narcisse were among the lowest ever recorded 
anywhere (King 1937, p. 525: Bump et al. 1947, 



p. 318: Palmer 1956: Dorney and Kabat 1960, p. 
36: Gullion and Marshall 1968, p. 145: Rusch 
and Keith 1971b, p. 815). 

Extrapolation from the grouse remains found 
on the 40-ha area searched and at three raptor 
nests suggests that raptors consumed at least 
one-half of the 18 grouse per day lost on the 
study plot in July-August 1971. This suggestion 
is tenuous because of our small sample sizes and 
imprecise indices to grouse numbers. On the 
other hand, it is unlikely that all of the grouse 
consumed by raptors were found in the search or 
tabulated at nests. In addition, Coyotes {Canis 
latrans). Red Foxes ( Vulpes vulpes). Goshawks 
{Accipiter gentilis), and Broad-winged Hawks 
{Buteo platypterus) were also seen on the study 
plot and all probably consumed some grouse. 
Thus predators may have accounted for more 
than one-half of the grouse lost. We feel, as did 
Bump et al. (1947, p. 3 1 7), Gulhon (1970b, p. 93), 
and Rusch and Keith (1971b, p. 818), that most 
of the grouse lost from the study population 
were probably killed by predators and consumed 
by them. 

Data presented in this paper are not ex- 
perimental, and are thus inconclusive, but 
support the hypothesis that cyclic declines in 
grouse numbers are caused by a shift in predator 
food habits duringor after a die-off of Snowshoe 
Hares. This hypothesis, appealing in its simpli- 
city, has been advanced by many other in- 
vestigators such as Cabot (1912), Burnham 
(1918), Hewitt (1921), Cox (1936), Grange( 1949, 
pp. 168 169), Lack (1954), Rusch and Keith 
(1971b), and Keith (1974, p. 45). 

On the other hand, this hypothesis was 
challenged by Hoffmann (1958) and Keith 
(1963) who showed that grouse sometimes 
declined before hares. Although most Tetraoni- 
dae populations are thought to be limited by 
mortality of young after the breeding season 
(Bendell 1970), grouse researchers generally feel 
that intrinsic factors such as territorial behavior 
and quality of the breeding stock, or extrinsic 
factors such as weather and food are more 
important than predation in the determination 
of grouse numbers. We suggest that high rates of 
predation are sufficient to cause grouse declines 
but are not necessarily involved in all declines. In 
addition, our data do not show whether 
the Ruffed Grouse at Narcisse were surplus or 



1978 



RUSCH ET AL.: RUFFED GROUSE, MANITOBA 



127 



debilitated, thus rendering them more vulner- 
able to predation. Thus the data presented here 
are also consistent with popular hypotheses of 
population regulation. No one explanation of 
grouse declines is likely to be widely accepted 
without field experiments and long-term studies 
of the prey and predator species involved in the 
10-year cycle. 

Acknowledgments 

This study was conducted and supported by 
the Research Branch of the Manitoba Depart- 
ment of Renewable Resources and Transporta- 
tion Services. We thank all the Department 
employees who assisted in various ways and 
acknowledge especially the field and administra- 
tive assistance of Charles Dixon, Kenneth Doan, 
Donald Glays, Ronald Lyon, and Ronald 
Weatherill. We thank William Creed, Gordon 
Gullion, Keith McCaffrey, John Moulton, Orrin 
Rongstad, and Fred C. Zwickel for helpful 
comments on the manuscript. 

Literature Cited 

Bendell, J. F. 1970. Population dynamics of the Tetraoni- 
dae: introduction to the symposium. International Or- 
nithological Congress 15: I ^ (abstract). 

Bump, G., R. W. Darrow, F. C. Edminister, and W. F. 
Crissey. 1947. The Ruffed Grouse: life history, pro- 
pagation, management. New York State Conservation 
Department, Holling Press, Inc., Buffalo, New York. 
915 pp. 

Burnham, J. B. 1918. Why grouse are scarce. Bulletin of the 
American Game Protection Association 7(1): 4-7. 

Cabot, W. B. 1912. In northern Labrador. Barger, Boston. 
292 pp. 

Cottam, G. and J. T. Curtis. 1956. The use of distance 
measures in phytosociological sampling. Ecology 37(3): 
451-460. 

Cox, W. T. 1936. Snowshoe rabbit migration, tick in- 
festation, and weather cycles. Journal of Mammalogy 
17(3): 216-231. 

Criddle, N. 1930. Some natural factors governing the 
fluctuations of grouse in Manitoba. Canadian Field- 
Naturalist 44(4): 77-80. 

Dorney, R. S. and C. Kabat. 1960. Relation of weather, 
parasitic disease, and hunting to Wisconsin Ruffed Grouse 
populations. Wisconsin Conservation Department, Tech- 
nical Bulletin Number 20. 64 pp. 

Eng, R. L. and G. W. Gullion. 1962. The predation of 
Goshawks upon Ruffed Grouse on the Cloquet Forest 



Research Center, Minnesota. Wilson Bulletin 74(3): 
227-242. 

Errington, P. L., Frances Hamerstrom, and F. N. Hamer- 
strom, Jr. 1940. The Great Horned Owl and its prey in 
north-central United States. Iowa State College Agri- 
cultural Experiment Station Bulletin 277: 757-850. 

Grange, W. B. 1949. The way to game abundance. Scrib- 
ner's. New York. 365 pp. 

Gullion, G. W. 1966. The use of drumming behavior in 
Ruffed Grouse population studies. Journal of Wildlife 
Management 30(4): 717-729. 

Gullion, G. W. 1970a. Factors affecting Ruffed Grouse 
populations in the boreal forests of northern Minnesota, 
USA. Finnish Game Research 30: 103-117. 

Gullion, G. W. 1970b. Factors influencing Ruffed Grouse 
populations. Transactions of the North American Wildlife 
and Natural Resources Conference 35: 93-105. 

Gullion, G.W. and W. H. Marshall. 1968. Survival of 
Ruffed Grouse in a boreal forest. Living Bird 7: 1 17-167. 

Hewitt, C. G. 1921. The conservation of the wild life of 
Canada. Scribner's, New York. 344 pp. 

Hoffman, R. S. 1958. The role of predators in "cyclic" 
declines of grouse populations. Journal of Wildlife 
Management 22(3): 317-319. 

Keith, L. B. 1963. Wildlife's ten-year cycle. University of 
Wisconsin Press, Madison. 201 pp. 

Keith, L. B. 1974. Some features of population dynamics in 
mammals. 11th International Congress of Game Biolo- 
gists, pp. 17-58. 

King, R. T. 1937. Ruffed Grouse management. Journal of 
Forestry 35(6): 523-532. 

Lack, D. 1954. Cyclic mortality. Journal of Wildlife Man- 
agement 181(1): 25-27. 

Leopold, A. 1933. Game management. Charles Scribner's 
Sons, New York and London. 481 pp. 

Palmer, W. L. 1956. Ruffed Grouse population studies on 
hunted and unhunted areas. Transactions of the North 
American Wildlife Conference 21: 338-345. 

Ransom, A. B. 1965. Observations of a Ruffed Grouse 
decline. Canadian Field-Naturahst 79(2): 128-130. 

Rusch, D. H. and L. B. Keith. 1971a. Ruffed Grouse- 
vegetation relationships in central Alberta. Journal of 
Wildlife Management 35(3): 417^29. 

Rusch, D. H. and L. B. Keith. 1971b. Seasonal and annual 
trends in numbers of Alberta Ruffed Grouse. Journal of 
Wildlife Management 35(4): 803-822. 

Rusch, D. H., E. C. Meslow, L. B. Keith, and P. D. Doerr. 
1972. Response of Great Horned Owl populations to 
changing prey densities. Journal of Wildlife Management 
36(2): 282-296. 

Seton, E. T. 1929. Lives of game animals. Volume4, Part 2. 
Doubleday, Doran and Company, Inc., Garden City, New 
York. 549 pp. 

Received 18 July 1977 
Accepted 2 December 1977 



Distribution and Density of Woodchuck Burrow 
Systems in Relation to Land-use Practices 

John A. Henderson and Frederick F. Gilbert 



Department of Zoology, University of Guelph, Guelph. Ontario NIG 2W1 

Henderson, John A. and Frederick F. Gilbert. 1978. Distribution and density of Woodchuck burrow systems in relation 
to land-use practices. Canadian Field-Naturalist 92(2): 128-136. 

Some 552 Woodchuck (Marmota monax rufescens) burrow systems, defined by both Woodchuck use and spatial 
considerations, were found on 85.7 ha of mixed farmland at Cambridge, Ontario between March and October 1973. The 
distribution of burrow systems for the entire study area did not differ significantly from a Poisson distribution, but densities 
differed with land use. The number of actively-used burrow systems per hectare averaged 5.9 and ranged from 1.8 in newly 
seeded pastures to 16.8 in undisturbed brushy fencerows. Uniform spacing in five fields was attributed to agnostic behavior 
primarily among juvenile Woodchucks during rapid invasion of new habitat. Ninety-one percent of all burrowing activity 
took place between April and July, and all new burrow systems were dug in recently cultivated areas. The rate of invasion of 
new habitat increased with the availability of vegetative cover. The number of burrow systems located in brushy fencerows 
remained virtually unchanged throughout the study. These fencerows served as Woodchuck "refuges" and repopulation 
centers for the adjacent cultivated fields. 

Key Words: Woodchuck, land use, dispersal, population, farm, refugia. 



The Woodchuck has been extensively studied 
with respect to its basic biology, primarily to 
elucidate physiological components of, and 
environmental factors affecting hibernation 
(e.g., Bailey 1965; Davis 1967) and changes in 
population status (e.g., Davis etal. 1964; Ludwig 
1976; Snyder 1962). Of more immediate concern 
to many land-owners, particularly farmers, 
however, is the burrowing activity of the species 
and the attendant aboveground piles of ex- 
cavated earth. 

Moss (1940) demonstrated that Woodchuck 
burrow systems were clustered in relation to soil 
texture. Merriam (1971), however, considered 
heterogeneity of the physical environment and 
biological attraction among Woodchucks to be 
important in causing clustering of burrow 
systems. De Vos and Gillespie (1960) noted that 
densities of burrow systems were considerably 
different from one field to another and they felt 
the distribution was influenced by land-use 
practices. 

The major objective of this study was to 
determine the distribution and density of 
Woodchuck burrow systems on mixed agri- 
cultural land as related to physiography, vege- 
tational characteristics, and land-use patterns. 

Materials and Methods 

The study was carried out between 3 March 
and 22 October 1973 on 85.7 ha of mixed 



agricultural land on University of Guelph 
property located in Cambridge, Ontario 
(80°20'N, 43°20'W). The soils originated pre- 
dominantly from sandy glacial tills. The surface 
layer, 20-66 cm in depth, was of a loam-to- 
gravelly-loam texture (Presant and Wicklund 
1971). Gravel, cobbles, and stones generally 
underlie the surface soil layer and soil drainage is 
good. 

Fences divided the study area into 14 units 
(Figure 1) representing six major types of land- 
use (Table 1; Figure 2). Three of the areas (1,4, 
and 9) had been in pasture for more than 10 years. 
The vegetation in these three areas, which was 
predominantly orchard grass (Dactylis glom- 
erata), clover (Trifolium hybridum), and dande- 
lion (Taraxacum officinale) in areas 1 and 4 and 
orchard grass, brome grass (Bromus inermus), 
and dandelion in area 9, was maintained at 
about 0.3 m or less during the summer months 
by periodic mowing to create a more vigorous 
forage crop. Three other areas (3, 5, and 8) had 
been hay fields and were harvested twice 
annually for at least 5 years prior to the study. 
Areas 3 and 5 were used for pasture purposes 
during 1973 as was area 8 in August after hay 
harvest. Area 3 contained primarily orchard 
grass, brome grass, and yellow foxtail (Setaria 
glaucaj, area 5 orchard grass and brome grass, 
and area 8 brome grass and clover. Because of 
the previous land-use history of these fields and 



128 



1978 



Henderson and Gilbert: Woodchucks and Land Use 



129 




Brushy Fencerows 
Fences 



Arbitrary Boundaries 

Figure 1. Map of study area showing land compartments 
and identification numbers. 




the limited impact of grazing in 1973, these fields 
were classified as hay fields. Area 6 had been in 
crops before being seeded with oats (Avena 
sativa), alfalfa (Medicago sativa), clover, and 
orchard grass in the spring of 1972. Cattle were 
allowed access to area 6 during August 1973. 

Table 1 — Locations (see Figure 1) and areas of major 
land-use types on the study area 



Land use 



Locations of 
land-use types 



Area 
(ha) 



Pasture 


1,4, 9 


16.4 


Hay 


3. 5, 6, 8 


23.5 


Wheat 


2 


10.8 


Seeded 


10. 11, 12 


24.5 


Woodlot 


7, 13 


4.9 


Fencerow 


Various locations 


5.6 



Figure 2. Photomap of the study area showing the land 
compartments in 1972. 



*There were appro.ximately 2800 m of brushy fencerows. 
The actual width of the row of vegetation was everywhere 
less than 10 m, but the effective width of influence 
on burrowing sites was estimated to be closer than 20 m 
owing to overhead cover and root systems. 

Area 2 had been in crops since 1969. It was 
planted with winter wheat {Triticum sp.) in the 
fall of 1972. After the wheat was harvested in 
early August 1973, this field was fertilized with 
manure and cultivated. 

Areas 10, 11, and 12 were plowed in the fall of 
1972, disked in May 1973, and seeded with 
bird's-fool trefoil (Lotus corniculatus) and 
timothy (Phleum pratense) in early June. All 
three areas had been used for grain crops for 
several years prior to 1973. The trefoil was 
mowed to a height of about 15 cm in early 
August and cattle were permitted to graze these 
fields starting the middle of September. All three 
fields were dominated by timothy and trefoil; 
dandelion, black medick (Medicago lupulina), 
green foxtail (Setaria viridis), and sand wort 
(Arenaria serpyllifolia) were also relatively 
abundant on area 10. Area 11 had some green 
foxtail and yellow foxtail and area 12 some green 
foxtail, sandwort, and old witchgrass (Panicum 
capillare). 

The two woodlots (areas 7 and 13) were 
mature stands consisting mainly of maples (/ic^"/' 
spp.), beech (Fagus grandifolia), and oaks 
{Quercus spp.). The herbaceous ground cover 
was mainly mayapple (Podophyllum peltatum), 
jewelweed (Impatiens biflora), jack-in-the- 
pulpit (Arisaema triphyllum), trilliums ( Trillium 



130 



The Canadian Field-Naturalist 



Vol. 92 



spp.), false Solomon's seal (Smilacina race- 
mosa), and a scattering of grasses (Gramineae). 

The approximately 2800 m of brushy fence- 
rows consisted of hawthorn {Crataegus sp.), 
cherry {Prunus sp.), oak, and several other 
woody species. The herbaceous plants included 
burdock (Arctium minus), milkweed (Asclepias 
sp.), goldenrod (Solidago sp.), blackberry 
(Rubus sp.), raspberry (Rubus sp.), and several 
grasses (Gramineae). 

The study area was gridded into 0. 16-ha 
squares (40 X 40 m). Wooden stakes, painted 
orange to improve visibility, were driven at grid 
intersects. Each square was identified on a map 
by a letter and number coordinate. The 
descriptions of field vegetation were made from 
25-cm square plots; each was positioned in a 
randomly selected quadrat, 2 m from the grid 
intersect, along a line bisecting the grid angle, 
i.e., 45 degrees off the grid lines. Ten percent of 
the grid intersects in each area were randomly 
selected to determine plot locations. Further 
vegetative data for the study area in 1973 is 
available from an ecological study (Lothian 
1974). A topographic map was prepared from 
slope data obtained with an Abney level (Mosby 
1971). Elevations were determined at 40-m 
horizontal spacing following the study area grid 
lines or at 20-m horizontal spacing where there 
was a noticeable change in slope between the 
grid stakes. Contour lines were interpolated at 
100-m intervals. 

The study area was mapped 1 7 April - 5 May, 
10 July- 16 August, 15 October -22 October to 
determine burrow locations. Actual dates of 
inventory were influenced by farm-management 
practices. Burrow systems were distinguished on 
the following considerations: all burrows 
> 10 m apart were considered to belong to 
separate systems; burrows < 10 m but > 3 m 
apart were assigned to a system only if they were 
connected by obvious trails, otherwise the 
burrows were considered to belong to separate 
systems; all burrows < 3 m apart were con- 
sidered to belong to a common system. 
Individual burrows were classified as open or 
closed. A closed burrow was partially or entirely 
plugged with earth as a result of erosion, 
disturbance by cattle, or by Woodchuck activity. 
In wooded sites, a closed burrow was usually 
plugged with leaf litter. Burrow systems were 



classified as active or inactive. An active system 
contained one or more open burrows at which a 
Woodchuck was trapped or sighted or at which 
there was fresh sign of Woodchuck activity. 

One hundred wooden boxtraps and 30 
commercial wire traps provided over 64 000 
trap-hours of effort. During the first trapping 
cycle (15 April 7 June) each area was trapped 
for 10 days. The time-frame was reduced to 5 
days for subsequent cycles (1 1 June - 6 July and 
30 July - 30 August) to reduce temporal 
variation between areas. All open burrow 
systems received equal trapping effort (± 10%) 
within each trapping cycle. Traps were kept 
within 3 m of the main burrow entrance but were 
not placed directly at the burrow entrance. Areas 
10, 11, and 12 were cultivated in May and could 
not be trapped. Area 13 (woodlot) was not 
trapped in the spring since all but eight burrow 
systems were still covered with leaves from the 
previous fall. 

Traps were checked at least every 3 h to 
minimize loss of Woodchucks to heat stress 
(Simpson 1912). Captured animals were re- 
strained in a burlap bag. Each Woodchuck was 
aged (Davis 1964), sexed, weighed, and per- 
manently marked by clipping toes. The time and 
exact location (by grid coordinates) of each 
capture were recorded. 

Burrow systems were tested for environmental 
correlates using Kendall's rank correlation 
modified for ties (Snedecor and Cochran 1967). 
Grid squares were used as the sample quadrats. 
Soil textural classes were ranked from 1 to 6 for 
the heaviest to the Hghtest soils respectively. 
Slope was derived from the contour map by 
measuring the change in elevation across grid 
squares. Scheffe's Test (Snedecor and Cochran 
1967) was used to compare mean burrow 
densities in the two drainage classes. Vegetation 
was not included because the amount of 
diversity between areas precluded a simple 
ranking system. 

The densities of burrow systems for the 
different areas were compared using Scheffe's 
Test (Snedecor and Cochran 1967). Areas were 
combined on the basis of present land use, and 
mean densities of burrow systems were again 
compared using Scheffe's Test. 

Spatial distributions of burrow systems were 
determined on the basis of the 0. 16-ha squares. 



1978 



Henderson and Gilbert: Woodchucks and Land Use 



131 



The distribution was tested using chi-square. As 
the detection of spatial pattern within a 
population could depend on the size of the 
sample quadrats, we calculated Morisita's Is- 
index (Greig-Smith 1964) for several quadrat 
sizes and graphed the values. The spatial pattern 
of burrow systems within fields was analyzed 
using Hopkin's coefficient of aggregation 
(Greig-Smith 1964). Since this method required 
an ideal sample size of 50 or more, only fields 2, 
3, 5, 6, and 8 were tested. The spatial pattern in 
these fields and in all other areas was also tested 
using chi-square. 

Results 

Of the 472 burrow systems mapped in April, 
80.3% were active. Between April and October, 
Woodchucks reactivated 63 old burrow systems, 
built 80 new systems, and abandoned 1 6 systems. 
All of the new burrow systems were dug in 
recently disturbed areas: 38 in the wheat field, 37 
in the seeded fields, and 5 in area 6. 

Most burrow systems had only one or two 
entrances in October owing to the large number 
of newly excavated systems (Table 2). In recently 
disturbed areas 90.5% of the systems had one or 
two entrances compared with 57.0% elsewhere 
(P < 0.01). Modification of entrances to burrow 
systems was greatest in pasture and hay fields 
and least in recently disturbed areas. There was 
no difference between the observed and a 



Poisson distribution of burrow systems. Burrow 
system densities, however, were significantly 
different between areas. Densities of burrow 
systems in areas 2, 9, 10, 11, and 12 were 
significantly lower (/'< 0.01) than in areas 8, 13, 
and 14. The density of burrow systems in area 10 
was significantly lower (/"< 0.01) than in areas 
3, 5, 6, 8, 13, and 14. 

The density of burrow systems per hectare was 
least (1.75) in the newly seeded fields. Pasture 
fields (4.70) and the wheat field (4.72) had 
similar densities as did hay fields and woodlots 
with 8.43 and 8.78 burrow systems per hectare 
respectively. The densities in hay fields and 
woodlots were significantly higher (P<0.01) 
than in pasture and wheat fields. Brushy 
fencerows, with 16.8 burrow systems per 
hectare, had the highest (P<0.0\) density of 
any land-use type (Table 3). 

The shape of the graph of Morisita l6-index 
values indicated either a uniform distribution or 
a contagious distribution with very large clumps, 
the inter-clump distribution being uniform 
(Iwao 1970). Clumping was not detected with a 
quadrat size of 1.44 ha but any further increase 
resulted in an invalid sample size. 

Based on nearest-neighbor measurements 
(Hopkin's coefficient of aggregation, Greig- 
Smith 1964), the spacing of burrow systems was 
significantly (P < 0.01) uniform in areas 2 and 8 
and approached uniformity in areas 3, 5, and 6. 



Table 2 — Frequency distribution of entrances per burrow system in October. (Tested for goodness of fit to 
Poisson distribution) 











Enti 


ranees 


per system 








Number of 


Area 


1 


2 


3 


4 


5 


6 


7 


8 


9 


10 


systems 


1 


2 


6 


7 


3 


4 


2 






1 




25 


2 


31 


15 


3 


2 














51 


3 


2! 


13 


2 


1 














55 


4 


7 


8 


5 


7 


2 


1 










30 


5 


6 


15 


10 


7 


3 


2 


1 




1 




45 


6 


8 


20 


10 


3 


3 






1 






53 


7 


4 


I 


3 


2 


3 




1 


1 






14 


8 


11 


20 


13 


5 


2 


8 


1 








53 


9 


6 


7 


6 


2 


1 












22 


10 


4 


3 


1 


1 








1 






10 


11 


14 


12 


1 
















27 


12 


4 


• 2 


















6 


13 


12 


7 


5 


3 


2 












29 


14* 


17 


38 


18 


9 


6 


3 


1 


1 




94 




Total 


147 


172 


95 


46 


27 


9 


3 


4 


2 


1 


506 



*Fencerows. 



132 



The Canadian Field-Naturalist 



Vol. 92 



Table 3 — Comparison of mean densities of burrow systems in each land-use type for April, July, and October 
(Scheffe's Test, P<0.05; compare differences with 2.88). (S) — seeded fields, (Wh) — wheat fields, (Wo) — woodlots, 
(P) — pastures. (H) — hay fields, (F) — fencerows 



Month 



burrow s\stems ha 



.April 

July 

October 



0.37 




l.ll 


< 


4.29 




4.45 


< 


7.37 


< 


16.1 


(S) 




(Wh) 




(Wo) 




(P) 




(H) 




(F) 


1.5! 


< 


4.57 




4.72 


< 


8.60 




8.78 


< 


16.8 


(S) 




(P) 




(Wh) 




(H) 




(Wo) 




(F) 


1.75 


< 


4.70 




4.72* 


< 


8.43 




8.78 


< 


16.8 


(S) 




(P) 




(Wh) 




(H) 




(Wo) 




(F) 



*Assumed density if wheat field had not been culti\ated in August. 



These results confirmed those from quadrat 
sampling. Since certain land-use types had 
densities of burrow systems greater than others, 
the clumping indicated by the Morisita test must 
have occurred at the field level or higher. The 
clumping of burrow systems in woodlot 7 was 
the only contagion observed within a habitat 
type. The burrows were associated with a 
number of woodpiles in this area. 

Burrow systems were significantly correlated 
with both slope and soil texture (Kendall's rank 
correlation, /*< 0.001). But soil texture and 
slope were themselves correlated (/'< 0.001). 

Area 5 provided an indication that slope may 
influence burrow location. Soil texture, drain- 
age, and depth and vegetation were all fairly 
uniform throughout the field. Over 60% of the 
field was nearly level, the remainder sloping 
moderately toward one side, yet more than half 
of the burrow systems were located on the slope 
(Kendall's rank correlation P< 0.01). In areas 2, 
6, and 8, however, burrow systems were equally 
abundant on level and sloped areas. 

It was not possible to test adequately the 
effects of soil texture on burrow sites in- 
dependent of other potential causes since soils of 
similar texture tended to occur in large blocks, 
closely corresponding to field areas. Areas 5 and 
6 (hay fields) were physiographically similar 
except for soil texture. Burrow system densities 
in the two areas were not significantly different. 
Conversely, areas 4 and 9 (pastures) differed 
markedly in nearly every feature except vegeta- 
tion and land use, yet burrow system densities 
were not significantly different in these areas. 

No consistent relationship was observed 
between burrow locations and drainage. Al- 



though the mean density of burrow systems in 
the imperfectly drained loams (3.70/ ha) was less 
than in well drained loams (5. 18/ ha), the 
difference was not significant. 

Our 64 728 trap-hours of effort resulted in 589 
Woodchuck captures for an average of 1 10 trap- 
hours per capture. There were significant 
seasonal changes in the effort needed to capture 
a Woodchuck. The reduced effort needed to 
capture a Woodchuck in May and June com- 
pared with April reflected the addition of young 
animals to the population (Table 4). The 
decrease in captures in August (350 trap-hours 
per Woodchuck) was due to an observed lower 
activity of all Woodchucks. Four hundred 
different Woodchucks were handled (Table 5). 
Seventy-six percent of all females, other than 
juveniles, were or had been lactating when 
captured. 

Distances between capture sites of 181 Wood- 
chucks caught two or more times averaged 
139.3 ± 94.5 m (Table 6). .Although recapture 
distances of juveniles were consistently greater 
than recapture distances of adults for both sexes, 
only the difference between adult and juvenile 
females (260.2 m and 75.0 m) was significant. 
Time between recaptures was similar for all 
groups and averaged 19.8 days. Between 18 
April and 20 June, 68% of recaptured adults and 
78.5% of recaptured juveniles were within 100 m 
of their previous capture site. In contrast from 23 
June to 30 August only 41% of recaptured 
juveniles were within 100 m of the previous 
capture site. During this latter time period 50% 
of the juveniles were relocated at more than 200 
m, while only 14.5% of the adults were recap- 
tured so far from the original capture site. 



1978 



Henderson and Gilbert: Woodchucks and Land Use 



133 



Table 4 — Temporal distribution of Woodchuck captures 








Total 


Number of captures 


Time period 
(trap-hours) 


Adults* Juveniles 


Males Females Males Females 



18 April - 10 May 
(9964 trap-hours) 

14 May - 7 June 
(10 170 trap-hours) 

1 1 June - 6 July 
(20 194 trap-hours) 

30 July - 30 August 
(24 400 trap-hours) 



124 

204 

186 

70 



72 
73 
12 
13 



52 
68 
24 
13 



31 

78 
30 



32 

72 



'Includes yearlings. 



Table 5 — Sex and age distribution of captured Woodchucks 



Sex 



Juvenile Adult Totals 



Males 
Females 
Totals 



90 


112 


94 


104 


84 


216 



202 



400 



Discussion 

DeVos and Gillespie (1960) reported 56% of 
the burrow systems they investigated in May as 
active. This value is considerably lower than the 
80% figure found in April for our study. The 
difference may be a function of disturbance due 
to fall plowing on our study area, forcing 
animals to use previously abandoned burrow 
systems for overwintering. The mean number 
of open entrances per burrow system in un- 
disturbed areas (2.81) was, however, similar to 
the 2.98 entrances per system reported by 
Merriam (1971). Merriam (1971) also noted an 
increase in the relative occurrence of one- and 
two-entrance burrow systems in October as was 
the case in this study. He attributed this change 



to observational errors caused by heavy ground 
cover. We found that newly dug burrow systems 
accounted for most of the one- and two-entrance 
systems and usually juveniles were captured at 
these sites. This supports the belief of earlier 
investigators (Hamilton 1934; Allen and Shap- 
ton 1942; de Vos and Gillespie 1960) that 
dispersing juveniles dig simple burrow systems 
usually with a single entrance. 

The density of burrow systems on the entire 
study area in October (5.94/ ha) was greater than 
the 3.52/ ha reported by de Vos and Gillespie 
(1960) for 68.2 ha of mixed farm land located 
about 30 km east of our study area. The main 
difference between the two farms was the 
inclusion on the latter of about 23 ha of old field 
that was dominated by largely inedible (Fall 
1971) plants such as devils' paint brush (Hiera- 
cium aurantiacum), common mullein (Verbas- 
cum thapsus), and goldenrod (Solidago spp.). 
Similarly a decrease in Woodchuck population 
density in Pennsylvania was attributed to ces- 
sation of active farming operations and resultant 



Table 6 — Distances between capture sites of Woodchucks by age and sex groups for Woodchucks caught two or more 
times (number of recaptures in brackets) 





Average distance between capture 
sites (m) 




Age 


Males Females 


Means 


Adults* 
Juveniles 
Means 


118.1 (60) 75.0 (49) 
170.9 (49) 260.2 (23) 
142.7 (109) 134.2 (72) 


98.7 (109) 
199.4 (72) 
139.3 (181) 



*Includes yearlings. 

NOTE: Standard Error of Estimates 



0.6834. 



134 



The Canadian Field-Naturalist 



Vol. 92 



plant succession (Ludwig 1976). Woodchuck 
populations are highest where active farming 
operations are occurring as the animals exploit 
such crops as alfalfa, clover, wheat, etc. (Hamil- 
ton 1934; Schoonmaker 1938; Grizzell 1955; de 
Vos and Gillespie 1960; MacClintock 1970). 
The pattern of burrow system density certainly 
reflected the animals' proclivity for field crops 
but was also influenced by such land-use 
practices as fall plowing and cultivation. 

Although the distribution of burrow systems 
over the entire study area was random, densities 
were considerably below the theoretical poten- 
tial based on burrow system measurements from 
other studies (Hamilton 1934; Allen and Shap- 
ton 1942; Grizzell 1955). Each grid square had 
the potential to contain 100 average burrow 
systems, yet the maximum observed was 10 and 
the average slightly less than 1 . The fields which 
had uniformly-distributed burrow systems were 
those which had been cultivated and were being 
invaded primarily by dispersing juveniles. Other 
studies (Moss 1940; Grizzell 1955; Merriam 
1971) have indicated a positive contagion in the 
spatial pattern of Woodchuck burrow systems. 
Only the woodlot (area 7), where Woodchucks 
had dug many burrows under piles of cordwood 
and logs, showed clustering of burrow systems. 
It would appear that factors other than food 
availability were responsible for the observed 
burrow system distribution. 

Merriam (1971) considered biological attrac- 
tion to be a necessary balance for agonistic 
group behavior. He found burrow systems to be 
in clusters on his study area and showed that 
movement pattern of the Woodchucks indicated 
systems within a cluster were more frequent than 
movements between clusters. He demonstrated 
that burrowing sites were influenced by soil 
drainage but he argued that the observed 
movement pattern of the Woodchucks indicated 
that biological needs other than suitable burrow 
sites, such as social facilitation of feeding 
behavior (Bailey 1965), may be satisfied by 
clustering of burrow systems. Social facilitation 
may be enhanced by clustering of burrow 
systems, but it was probably not a cause of the 
clustering. There is much evidence that social 
attraction does not occur during the summer 
(Bronson 1963, 1964; Smith 1972). The inter- 
burrow movement patterns observed by Mer- 



riam ( 1 97 1 ) could possibly be explained in terms 
of a restriction of movements by Woodchucks to 
their 'home ranges' (Smith 1972). 

The evidence that environmental heterogeneity 
may cause clustering of burrow systems is much 
stronger. Moss (1940) demonstrated a nearly 
complete restriction of burrows to certain soil 
textural classes. Merriam (1971) found drainage 
to be important in producing a clustering of 
burrow systems. In this study there was no area 
where physiographic conditions prevented 
Woodchucks from burrowing. Burrow systems 
were significantly correlated with both slope and 
soil texture, but soil texture and slope were 
themselves correlated. Furthermore, there was 
no difference between the observed and a 
random distribution of burrow systems for the 
whole study area but there were significant 
differences in the density of burrow systems 
between land-use types. Burrow systems were 
distributed randomly in 10 of the 13 areas 
studied. According to Odum (1971, p. 205), 
random distributions usually occur where the 
environment is very uniform and there is no 
tendency for the individuals in a population to 
aggregate. Both of these conditions were satis- 
fied within land compartments in the present 
study situation. Physiography did not signifi- 
cantly influence the location of burrows within 
land-use types since areas with similar soil 
texture and slope tended to occur in large blocks 
closely corresponding to field units. Soil drain- 
age was classed as good on 91.6% of the study 
area, so it was unlikely to influence the siting of 
burrow systems. 

The difference in the densities of burrow 
systems between areas was apparently caused by 
environmental heterogeneity associated with 
agricultural practices. The most noticeable effect 
of agriculture was its influence on the vegetation. 
All fields were artificially planted, making plant 
species and densities relatively uniform within 
fenced areas but markedly different between 
areas. The qualities of vegetation also differed 
greatly between land-use types and were modi- 
fied by mowing and harvesting and by grazing of 
cattle. These differences were independent of 
physiography. The use of organic and chemical 
fertilizers would reduce the differentiating 
effects of any natural environmental variability 
on the quality and quantity of vegetation. Thus 



1978 



Henderson and Gilbert: Woodchucks and Land Use 



135 



the effects of cultural practices would account 
for most of the differences in vegetation between 
land-use types, and this in turn would influence 
the activity of Woodchucks in an area. 

The efforts of farm personnel to reduce 
Woodchuck numbers by gassing and shooting, 
although successful in increasing mortality 
probably caused a shift in the age structure of the 
population toward a preponderance of younger 
animals rather than a decrease in population 
size. Increased productivity of yearling females 
and a decreased net emigration of juveniles 
could combine to produce such an effect (Snyder 
1962; Barash 1973). Data from the present study 
indicated that nearly 60% of yearlings lactated. 
This was equivalent to the maximum value 
found by Synder (1962) for an area where a 
Woodchuck population had been experimen- 
tally reduced. 

Increased reproduction by yearlings enables 
Woodchucks rapidly to repopulate recently 
cultivated land. De Vos and Gillespie (I960) 
gave two examples of a relationship between 
cultivation of a field and its subsequent rein- 
vasion by Woodchucks. One field of unspecified 
size was fall plowed, left in fallow for a year and 
planted with alfalfa, clover, and timothy the 
following spring. For the 5 years following 
plowing, the number of burrow systems was 1,1, 
8, 11, and 13. Another 4.5-ha field was plowed 
and seeded to alfalfa, clover, and timothy. The 
Woodchuck population remained at a low level 
for the following 6 years. These findings do not 
agree with those of the present study where 47 
burrow systems were mapped in a 5.3-ha hay field 
only 1 year after being plowed and seeded to 
alfalfa, clover, oats, and orchard grass. Only five 
new burrow systems were added to this field 
during the second summer following plowing, 
indicating that the density of burrow systems 
was near saturation after only one season. The 
only apparent difference between the two study 
situations was that a cover crop of oats was 
planted in this study. Although it is not directly 
comparable with the above findings, 38 burrow 
systems were excavated in the 10.8-ha wheat 
field in only 4 months. Again the wheat crop 
would have provided cover for the Woodchucks. 
But perhaps more important than cover in the 
rapid exploitation of these fields would be the 
high productivity of this population and the 



availability of large numbers of dispersing 
juveniles. The great mobility of Woodchucks, 
particularly of juveniles, assured the invasion of 
unoccupied land. Juveniles moved about very 
little during their first month aboveground but 
when they did become active, they travelled 
much farther than adults. Bronson ( 1 963) stated 
that adults made an insignificant contribution to 
the transient population and related it to their 
high relative rank. The ability rapidly to rein- 
vade disturbed habitat would have considerable 
survival value, enabling Woodchucks to main- 
tain high populations where crop rotation is 
practiced. 

Brushy fencerows occupied only 6.4% of the 
study area yet contained 20.8% of all active 
burrow systems in July. This high density of 
burrow systems and the great seasonal stability 
in both the number of burrow systems and the 
number of entrances per system suggest that this 
habitat was of particular importance to the 
Woodchuck population. These areas were sub- 
jected to minimal disturbance from climatic 
influences and farm operations and likely served 
as both 'refuges' for Woodchucks displaced by 
cultivation of adjacent areas and as repopulation 
centers (as a source of juvenile animals) for the 
cultivated fields. 

In woodlot area 13 only one Woodchuck was 
captured from nearly 3000 trap-hours of effort 
yet 22 closed burrow systems were reactivated 
between April and July. Grizzell (1955) believed 
that Woodchucks hibernated on wooded sites 
and moved to summer dens in crop and pasture 
areas. This is possible but unlikely in the present 
study since emergence from hibernation should 
have been complete (Smith 1972) before the 
woodlot was mapped in April and should have 
resulted in many burrows being opened. Eastern 
Cottontails (Sylvilagus flohdanus) were fairly 
numerous on the farm (seven rabbits were 
trapped in this woodlot) and could have opened 
many burrows, since entrances were usually 
blocked only with leaves (Hamilton 1934). This 
was unlike the field areas where more discernible 
sign was usually left which allowed identification 
of the species opening the burrow. Also there 
were three active Red Fox (Vulpes vulpes) dens 
in this woodlot. Foxes are the most important 
natural predator of Woodchucks (Grizzell 1955; 
Scott and Klimstra 1955) and could have been 



136 



The Canadian Field-Naturalist 



Vol. 92 



instrumental both in opening up burrows and in 
causing a decline in the Woodchuck population 
of the woodlot. Finally, the timing of part of the 
trapping effort (25-30 August) may have been 
partially responsible for the low number of 
captures as only 10 trap-days were involved for 
this area. 

In summary, it was apparent that Wood- 
chucks respond to man-made alterations in the 
environment by the juvenile segment of the 
population invading new habitat sites as cover 
and food conditions become suitable for ex- 
ploitation. The ability to exploit continually and 
rapidly such new habitat conditions appears 
dependent on unaltered habitat being readily 
available adjacent to the disturbed sites. The 
pattern of land use on most mixed farming units, 
at least in southern Ontario, appears to provide 
just such conditions and undoubtedly explains 
the high Woodchuck densities found in areas 
where soil texture and drainage are suitable for 
the species. 

Acknowledgments 

Field assistance was provided by B. Hender- 
son, T. Kellar, and D. Lothian. Land-use history 
and Woodchuck-control information were pro- 
vided by William McLean, former farm man- 
ager. Statistician J. Hines provided assistance 
with computer programing and statistical an- 
alysis of the data. Financial support was received 
from the Canadian National Sportsmen's Show. 

Literature Cited 

Allen, D. L. and W. W. Shapton. 1942. An ecological 

study of winter dens, with special reference to the eastern 

skunk. Ecology 23: 59-68. 
Bailey, E. D. 1965. The influence of social interaction and 

season on weight change in Woodchucks. Journal of 

Mammalogy 46: 438-445. 
Barash, D. P. 1973. The social biology of the Olympic 

marmot. Animal Behaviour Monographs 6: 172-245. 
Bronson, F. H. 1963. Some correlates of interaction rate in 

natural populations of Woodchucks. Ecology 44: 637- 

643. 
Bronson, F. H. 1964. Angonistic behaviour in Wood- 
chucks. Animal Behaviour 12: 470-478. 
Davis, D. E. 1964. Evaluation of characters for determin- 
ing age of Woodchucks. Journal of Wildlife Management 

28: 9-15. 
Davis, D. E. 1967. The annual rhythm of fat deposition in 

Woodchucks (Mannota monax). Physiological Zoology 

40: 391-402. 
Davis, D. E., J. J. Christian, and F. Bronson. 1 964. Effects 

of exploitation on birth, mortality and movement rates 



in Woodchuck population. Journal of Wildlife Manage- 
ment 28: 1-9. 

De Vos, A. and D. I. Gillespie. 1960. A study of Wood- 
chucks on an Ontario farm. Canadian Field-Naturalist 
74: 130-145. 

Fall, M. W. 1971. Seasonal variations in the food con- 
sumption of Woodchucks (Mannota monax). Journal 
of Mammalogy 52: 370-375. 

Greig-Smith, P. 1964. Quantitative plant ecology. Butter- 
worth and Co. (Canada) Ltd.. Toronto. 256 pp. 

Grizzell, R. A., Jr. 1955. A study of the southern Wood- 
chuck, Marmota monax monax. American Midland 
Naturalist 53: 257-293. 

Hamilton, W.J. , Jr. 1934. The life history of the Rufescent 
Woodchuck, A/ar/j/ora monax rufescens Howell. Ameri- 
can Carnegie Museum 23: 85-178. 

Iwao, S. 1970. Problems of spatial distribution in animal 
population ecology. Volume 2. In Random counts in 
scientific work. Edited by G. P. Patil. Pennsylvania State 
University Press, University Park. pp. 117-149. 

Lothian, D. C. 1974. Cruickston Park Farm ecological 
study. University of Guelph Report, Guelph, Ontario. 
158 pp. 

Ludwig, J. R. 1976. Decline of a Woodchuck population 
and compensation for reduction at low density. Ph.D. 
thesis. Southern Illinois University, Carbondale. 196 pp. 

MacClintock, D. 1970. Squirrels of North .'\merica. Van 
Nostrand Reinhold, New York. 184 pp. 

Merriam, H. G. 1971. Woodchuck burrow distribution 
and related movement patterns. Journal of Mammalogy 
52: 732-746. 

Mosby, S. 1971. Reconnaissance mapping and map use. 
In Wildlife management techniques. Edited by R. H. 
Giles. 3rd edition. Wildlife Society, Washington, 
pp. 119-134. 

Moss, A. E. 1940. The Woodchuck as a soil e.xpert. 
Journal of Wildlife Management 4: 441-443. 

Odum, E.P. 1971. Fundamentals of ecology. W. B. 
Saunders Co., Toronto. 574 pp. 

Presant, E. W. and R. E. Wicklund. 1971. Soils of 
Waterloo County. Number 44. Ontario Soil Survey, 
Research Branch, Canadian Department of Agriculture 
Report. 104 pp. 

Schoonmaker, W. J. 1938. The Woodchuck: lord of the 
clover field. Bulletin of the New York Zoological 
Society 41: 2-12. 

Scott, T. G. and W. D. Klimstra. 1955. Red fo.xes 
and a declining prey population. Southern Illinois 
University Monograph Series 1. 123 pp. 

Simpson, S. 1912. Temperature regulation in the Wood- 
chuck {Marmota monax). American Journal of 
Physiology 29: xii-xiv. 

Smith, M. C. 1972. Seasonal variation in home ranges of 
Woodchucks. M.Sc. thesis. University of Guelph. Guelph. 
Ontario. 67 pp. 

Snedecor, G. W. and W. G. Cochran. 1967. Statistical 
methods. Iowa State University Press, Ames. 593 pp. 

Synder, R. L. 1962. Reproductive performance of a popu- 
lation of Woodchucks after a change in sex ratio. 
Ecology 43: 506-515. 

Received 18 July 1977 
Accepted 5 December 1977 



Vascular Plant Range Extensions to the Heart Lake 
Area, District of Mackenzie, Northwest Territories 



William J. Codv and Stephen S. Talbot2 

'Biosystematics Research Institute, Agriculture Canada, Ottawa, Ontario Kl A 0C6 
-Department of Botany, University of Alberta, Edmonton, Alberta T6G 2E9 
Present address: Forest Management Institute, Environment Canada, Ottawa, Ontario KIG 3Z6 

Cody, William J. and Stephen S. Talbot. 1978. Vascular plant range extensions to the Heart Lake area, District of 
Mackenzie, Northwest Territories. Canadian Field-Naturalist 92(2): 137-143. 

The Heart Lake study area is briefly described. Two taxa, Eleocharis compressa and Rhynchospora alba, are reported from 
the continental Northwest Territories for the first time, and extensions of range for 19 additional taxa within the District of 
Mackenzie are recorded. 

Key Words: vascular plants. District of Mackenzie, Northwest Territories, Eleocharis compressa, Rhynchospora alba. 



In spite of increased interest and investigation 
of the North American boreal flora, large gaps 
still remain in our knowledge. Accordingly, this 
paper presents some of the more interesting 
plant records obtained from an extensive plant 
collection made in the Heart Lake area. The 
collection was made in conjunction with a 
phytosociological investigation (Talbot 1978) of 
the terrestrial and aquatic plant communities 
occurring in a representative portion of a small 



watershed within the boreal zone of southern 
District of Mackenzie. 

The Heart Lake area (Figure 1) is located 
18 km southwest of Great Slave Lake and is 
bounded by the geographical coordinates of 
60°48' and 60°53'N and of 116°37' and 
116°43'W. The study area surrounds Heart 
Lake, is irregular in shape, and is approximately 
30 km^ in size. 

Primary contributions to our knowledge of 




BRITISH COLUMBIA 



Figure 1. Location of Heart Lake study area in southern District of Mackenzie. 



137 



138 



The Canadian Field-Naturalist 



Vol. 92 



the area include the botanical investigations of 
the Wood Buffalo, Athabasca - Great Slave, 
and southwestern Mackenzie regions (Raup 
1935, 1936, 1946, 1947); the bogs and forests of 
northwestern Alberta (Moss 1953a, b), and the 
flora and vegetation adjacent to the Yellowknife 
section of the Mackenzie Highway (Thieret 
1963, 1964). 

Study Area 

Heart Lake lies in the southern portion of 
Great Slave Plain in the Interior Plains region 
(Bostock 1970a, b). Great Slave Plain is 
predominantly low-lying, almost flat ground 
usually below 300 m in elevation. It is charac- 
terized by low scarps of resistant carbonate 
strata, small shallow lakes, and organic terrain. 

The entire western basin of Great Slave Lake 
is underlain by calcareous Upper Devonian 
bedrock (Douglas 1974). 

Immediately after the retreat of ice, glacial 
Lake McConnell was formed, inundating a vast 
expanse, including Heart Lake. It extended from 
Great Bear Lake in the north through Great 
Slave Lake to Lake Athabasca in the south. 
Ancient postglacial beach ridges formed by the 
lake are prevalent within the Heart Lake area. 

The climate of the area is cold, continental 
(Harris and Calder 1975). Hay River, the nearest 
climatic station 40 km to the east, has a mean 
annual temperature of -3.7° C and averages 
340 mm precipitation annually. Over half the 
precipitation falls in the vegetative season. 
Summers are warm with a mean July tempera- 
ture of 20.6°C. 

The climatic subzone to which Heart Lake 
belongs may be calculated (Hamet-Ahti et al. 
1974) using Holdridge's (1967) bioclimatic 
index, the mean annual "biotemperature." If 
compared on the criterion of biotemperature, 
the following stations which encompass Heart 
Lake are "middle boreal": Hay River (biotempe- 
rature, 5.1°C), Fort Simpson (5.1°C). Fort 
Smith (4.9°C), and Fort Providence (4.8°C). 

With respect to Rowe's "Forest Regions of 
Canada," Heart Lake lies in the Hay River 
Section, B18b which "represents the northern 
extension of the mixedwood forest, somewhat 
modified by a more rigorous climate (colder and 
drier)" (Rowe,1972, p. 37). 

The predominant upland vegetation consists 



of coniferous and mixed woodlands with Pinus 
banksiana, Picea glauca, Populus tremuloides, 
Alnus chspa, Salix bebbiana, Rosa acicularis, 
Shepherdia canadensis, Juniperus communis, 
Arctostaphylos uva-ursi, and Elymus innovatus. 
Lowland vegetation consists of three major 
components: (1) wooded fens dominated by 
Picea mariana, Larix laricina, Betula glandu- 
losa, Potentilla fruticosa, Myrica gale, Salix 
Candida, S. myrtillifolia, Arctostaphylos rubra, 
Equisetum pratense, and Mitellanuda;{2) raised 
ombrotropic plateau bogs dominated by Picea 
mariana. Ledum decumbens, L. groenlandicum, 
Chamaedaphne calyculata, Andromeda poli- 
folia, Oxycoccus microcarpus, and Sphagnum 
fuscunr, and (3) reticulate string fens or aapa- 
mires whose surface is composed primarily of 
eutrophic wet hollows dominated by Carex 
aquatilis, C. limosa, Scirpus caespitosus, 
Menyanthes trifoliata, Drepanocladus revol- 
vens, and Scorpidium scorpioides. 

Flora 

The vascular flora of Porsild and Cody's 
(1968) sixth phytogeographic province, which 
includes Heart Lake, numbers about 573 taxa 
with the total flora for the continental North- 
west Territories numbering about 1135 taxa. 
Accordingly the relatively small Heart Lake area 
with 317 taxa (Talbot 1978) possesses 55.5% and 
28.0% of these floras, respectively. 

To a large degree the comparatively rich Heart 
Lake flora may be accounted for by landscape 
diversity, which provides a number of habitats. 
Examples include mesic escarpment canyons, 
talus, beach ridges, plateau-like uplands, raised 
bogs, string fens, lakes, streams, and both 
wooded and non-wooded fens. 

The following species have been identified and 
documented by a representative set of voucher 
specimens deposited in the herbarium of the 
Biosystematics Research Institute, Ottawa 
(DAO). Species taxonomy follows Porsild and 
Cody (1968). 

Ophioglossaceae 

Botrychium virginianum ssp. europaeum. Roadcut in 
white spruce fen with Petasiies and Carex. about 0.8 mi NE 
of Mile 81 Mackenzie Highway, Talbot 3748. This is a 
circumpolar subspecies which is found across boreal 
Canada, but in the District of Mackenzie previously known 
only from the foothills and slopes of the southern Mackenzie 

Mountains (Raup 1947; Cody 1963; Scotterand Cody 1974). 



1978 



Cody and Talbot: Vascular Plants, NWT 



139 



Polypodiaceae 

Cystopteris montana. In limestone canyon below escarp- 
ment. Mile 81.6 Mackenzie Highway, 60°55'N, 116°37'W, 
Talbot s.n., 23 July 1971. Thieret {I961)gathered aspecimen 
on the slope above Kakisa River, 2.4 km below Lady Evelyn 
Falls. This and the collection cited above are the only known 
localities for the species near Great Slave Lake, and are the 
easternmost yet found in the District of Mackenzie. It is a 
rare species in the district, being otherwise known only from 
Nahanni Mountain and between Nahanni Butte and Fort 
Simpson (Raup 1947), and indeed is rare elsewhere in 
Canada because of its special springy or damp calcareous 
habitat requirements. 



Potamogetonaceae 

Potamogeton natans. Shallow pond in eutrophic wet-level 
fen, about 1.3 mi S of Mile 92 Mackenzie Highway, Talbot 
3700. This is the second record of this pondweed for 
Mackenzie District. It is intermediate between the previously 
known site of Rabbitkettle Lake in the southern Mackenzie 
Mountains and the nearest sites to the south and southeast in 
southwestern Alberta and Lake Superior (Cody and Porsild 
1968; Scotter and Cody 1974). Two other interesting records 
have been found at this same site, one reported here, 
Rhynchospora alba, and one reported previously, Sarra- 
cenia purpurea (Cody and Talbot 1973). 

Cyperaceae 

Carex filifolia. Lithic regosol on subarctic heath 0.5 mi N 
of Mile 80, Mackenzie Highway 60°50'N, 1 16°37'W, Talbot 
218. Populations in the District of Mackenzie, Yukon 



Territory, and southeastern Alaska appear to be disjunct 
from those of the southern Prairie Provinces ( Figure 2). The 
species is rare in the District of Mackenzie, previous 
collections having come from Nahanni Butte (Scotter and 
Cody 1974) and Wrigley (Porsild 1951). 

Care.x interior. Wet sedge fen, about % mi N of Heart Lake 
Biological Station, Talbot 2313. Thieret ( 1 96 1 ) reported this 
species as new on. the basis of a collection at Mile 6! 
Mackenzie Highway, about 32 km distant from the site 
reported here. Elsewhere in the district it has since been 
found by hotspring ponds in the lower South Nahanni River 
area (Scotter and Cody 1974). It is a boreal species in North 
America. 

Carex livida var. grayana. Calcareous muck, about % mi 
N of Heart Lake Biological Station, Talbot 2307, shrub 
fen along lake margin, south end of Heart Lake, 
Talbot 6052. Carex livida s. lat. is a circumpolar species 
comprised of several disjunct populations. The var. grayana 
is found in North America from Newfoundland to Alaska 
and is boreal in its range. In the District of Mackenzie it was 
previously known only from the Eskimo Lake Basin (Porsild 
1943). 

Carex richardsonii. Subarctic heath on lithic regosol, with 
Juniperus horizontalis. Arctostaphylos uva-ur.si, Cladonia 
pvxidata, Ditrichum flexicaule, about 0.5 mi S of Heart Lake 
Biological Station, '60°50'N, 116°37"W, Talbot 247; Pine 
Point, 60°50'N, 114°20'W, Ducruc 165.17 (QFA, Photo 
DAO). The original description of this species gave the 
locality of "W," meaning "the wooded country between 54° 
and 64° N." This, however, did not mean that it occurred as 
far north as 64°, but only that it was found between those 



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limits. Raup (1936, 1947) collected the first District of 
Mackenzie specimen with accurate locality and data at Fort 
Smith, whence Cody {3801, 4036) later collected it. The 
specimens cited here extend the known range to near the 
upper Mackenzie River and thus confirm the prophecy of 
Raup (1947) that it would be found there. Carex richardsonii 
is a North American species which is found from the Great 
Lakes region west to interior British Columbia, northward 
slightly beyond latitude 60° N. 

Eleocharis compressa. Calcareous mud N of Heart Lake 
Biological Station, 60°5rN, 1 16°37'W, Talbot 2310, 3742. 
New to the District of Mackenzie. This represents a 
considerable extension of the known range from Jasper in 
southwestern Alberta (Figure 3). Eleocharis compressa is 
readily distinguished from other species of Eleocharis known 
in the district by its three-cleft rather than two-cleft style. 

Kobresia simpliciuscula. Wet fen with Scirpus caespito- 
sus, Triglochin mariiima, Drosera anglica, about -% mi N of 
Heart Lake Biological Station, Talbot 2304: in rich Scirpus 
caespitosus fen below escarpment, about 0.3 miNW of Heart 
Lake Fire Tower, Talbot 7303; rich sedge fen, about 0.4 mi 
NE of Heart Lake Biological Station, Talbot 9063. This is a 
circumpolar species which in Canada is found from 
Newfoundland to Alaska north to Ellesmere Island. It is 
apparently rare in the lowland area west of Great Slave Lake. 

Rhynchospora alba. Eutrophic wet-level fen with Sar- 
racenia purpurea, about 1.3 mi S of Mile 92 Mackenzie 
Highway, 60°54'N, 116°55'W, Talbot 3701. This species, as 
can be seen from the map ( Figure 4), has been found in many 
bogs in eastern Canada. It is known from several stations in 
Saskatchewan, and again in Alaska and the coastal parts of 



British Columbia. It is apparently absent in the extreme 
western part of Ontario, Manitoba, Alberta, and the interior 
parts of British Columbia, but should be looked for there in 
suitable habitats. The collection cited above is an extension 
of range of some 423 km to the northwest from Little Gull 
Lake south of Lake Athabasca in Saskatchewan (Argus 
1968). It is new to the flora of the continental Northwest 
Territories. The somewhat similar R. capillacea is known 
from marl bogs in all three prairie provinces, but is 
apparently rare there. It can be distinguished from R. alba b\ 
its spikelets which are deep brown to castaneous rather than 
white or whitish-brown, three rather than mostly two 
stamens, and 6 rather than 10 to 12 bristles. 

Orchidaceae 

Cypripedium calceolus var. parviflorum. Black spruce fen, 
about 1 mi NE of Mile 84, Mackenzie Highway, Talbot 4603. 
The map in Hulten ( 1968) indicates se\eral North American 
populations. In the District of Mackenzie this species was 
previously known from adjacent to the Liard and Mackenzie 
Rivers north to Great Bear Lake, and in the Mackenzie 
Mountains, it is apparently absent in northern Alberta and 
northern Saskatchewan and is certainly rare in the Great 
Slave Lake region from which the specimen cited here was 
obtained. 

Cypripedium guttatum. Picea glauca - feathermoss com- 
munity along riverbank, Kakisa River, 60°58'N, 1 17° 17'W, 
Talbot & Dyke 4601. This specimen is from the most 
southeasterly locality yet known in the District of 
Mackenzie. The species is Amphi-Beringian and extends 
across Alaska, Yukon, and the Mackenzie Mountains to 
Great Bear Lake and the Mackenzie River and two sites on 



1978 



Cody andTalbot: Vascular Plants, NWT 



141 







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the north and east arms of Great Slave Lake and the Kakisa 
River site reported here. 

Caryophyllaceae 

Arenaria humifusa. Picea tnariana - Tomenthypnum 
nilens fen, about 1 14 mi N of Heart Lake Biological Station, 
Talbot 4066. This is a rare plant in southwestern District of 
Mackenzie. The present collection helps complete our 
knowledge of its occurrence between the east end of Great 
Slave Lake and the Mackenzie Mountains. 

Ranunculaceae 

Ranunculus abortivus. Under eves of cabin where water 
runoff from roof collects. Heart Lake Biological Station, 
Talbot 2250. This is a boreal species which is known from the 
District of Mackenzie only from west of Fort Smith, from 
Nahanni National Park (Cody 1956; Scotter and Cody 
1974), and the collection cited above. 

Cruciferae 

Draba oligosperma. Lithic (calcareous-sandstone) regosol 
along escarpment edge, about 0.5 mi N of Heart Lake 
Biological Station, Talbot 2055 (det Mulligan). This is a 
Cordilleran species. According to Mulligan (1972), Draba 
oligosperma is one of the most common species of Draba in 
the mountains of the western United States. It is, however, 
only locally common in Canada, and in the District of 
Mackenzie was previously known only from the southern 
Mackenzie Mountains adjacent to the Liard River, about 
Great Bear Lake and adjacent to the Mackenzie River Delta. 
This extension of range to the lowland region at the west end 
of Great Slave Lake is thus of considerable interest. 



Lesquerella arctica. Lithic (calcareous-sandstone) regosol 
along escarpment edge, about 0.5 mi N of Heart Lake 
Biological Station, Talbot 2024. This is a North American 
arctic and alpine species which is found also in eastern 
Siberia. The nearest known sites to that reported above are in 
the southern Mackenzie Mountains(Raup 1947; Scotterand 
Cody 1974). 

Rosaceae 

Potentilla arguta. Lithic regosol in Juniperus communis 
barrens, about 0.5 mi NE of Mile 78 Mackenzie Highway, 
Talbot 4663; rare in partial shade of Populus tremuloides 
and Sali.x west of Le Grand Detour, Slave River, 60°2rN, 
1 1 2°44'W, Cody 13977; occasional in dry sedge-grass prairie 
near Hook Lake, 3 mi E of Slave River, Cody 14117. Thieret 
(1961) reported this species as new to the District of 
Mackenzie on the basis of specimens collected along the 
Yellowknife Highway, NW of Fort Providence. Scotter 
(1966) reported a second collection from Blachford Lake, N 
of the east arm of Great Slave Lake. The specimens cited 
above from the prairies of the Slave River and from near 
Heart Lake help complete our knowledge of the distribution 
of this rare plant in the district. In Wood Buffalo Park. 
Alberta, Raup (1936) reported this cinquefoil as "common in 
dry prairies and rock crevices." 

Ericaceae 

Oxycoccus quadripetalus. Raised bog, southeast corner of 
Heart Lake, Talbot 2360. This is a boreal species which 
apparently is quite rare in the District of Mackenzie. 
Previous collections were from Norman Wells (Cody 1960, 
sub Vaccinium oxycoccus) and along the Liard River 
(Jeffrey 1961). 



142 



The Canadian Field-Naturalist 



Vol. 92 



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Gentianaceae 

Genliana affinis. Rich organic hummock above wet marl, 
about 4 mi N of Mile 180 Mackenzie Highway, Talbot 468 1 . 
The presence of this species in the District of Mackenzie was 
first reported by Cody and Porsild (1968) on the basis of 
collections from the Keele River in the Mackenzie 
Mountains and near Fort Good Hope. Additional localities 
have since been found in the Keele River valley (Cody 1978), 
but the collection reported here helps fill in the gap between 
latitude 54° in southern Alberta and the Keele River sites. 
The species was rare at the present site. 

Scrophulariaceae 

Pedicularis parviflora. Shrub fen near inlet stream, 
southern Heart Lake, Talbot 3702: common in wet fen 
hollows between Sphagnntn hummocks near Tetcho Lake, 
60°25'N, 120°45'W, SE of Trout Lake, Rowe 1795 (DAO). 
This is a plant of spotty distribution in the central part of its 
range; it is apparently frequent in the lowlands adjacent to 
Hudson and James Bay in the east, and again on the Pacific 
coast. There is an early report (Macoun 1884) of P. palustris 
var. wlassoviana "On the Mackenzie River (McGill Coll. 
Herb.)," but we have been unable to locate and verify this 
collection. The collections cited above are thus the first 
verified record of P. parviflora occurring in the District of 
Mackenzie. They represent an extension of range NW from 
the only other Mackenzie Basin collection on the north shore 
of Lake Athabasca in Saskatchewan (Raup 1936). In 
Alberta, the nearest collection site is apparently Pigeon 
Lake, whence G. H. Turner made several collections (DAO). 
In the continental Northwest Territories it is also known 
from the Coastal Plain of Hudson Bay at the mouth of the 
McConnell River in the District of Keewatin (Cody and 
Porsild 1968). 



Lobeliaceae 

Lobelia kalmii. Rich shrub fen, about I mi N of Mile 81.7 
Mackenzie Highway, Talbot 4673. This is a rare plant in the 
District of Mackenzie, which is now known from several 
collections in the lowlands W of Great Slave Lake and about 
hot springs in the southern Mackenzie Mountains (Raup 
1936, l947;Thieret 1963; Scotter and Cody 1974). Although 
Hooker (1829-1840) reported this species as "in saline 
marshes in lat. 60°," L. kalmii is apparently not otherwise 
known from north of lat. 54°30" (Cold Lake) in eastern 
Alberta except for a site in northern British Columbia at the 
Liard Hotsprings (Figure 5). 

Acknowledgments 

The research was supported by National 
Research Council of Canada Grant A2570 to 
G. H. La Roi, and a Boreal Institute Grant-in- 
aid 1971-1973 (ST.). Appreciation is expressed 
to W. A. Fuller, Department of Zoology, 
University of Alberta for use of the facilities at 
the Heart Lake Zoological Station. 

Literature Cited 

Argus, G. W. 1968. Contributions to the flora of boreal 

Saskatchewan. Rhodora 70: 200-214. 
Bostock, H. H. 1970a. Physiographic subdivisions of 

Canada. In Geology and economic minerals of Canada. 

Edited by R. J. W. Douglas. Economic Geology Report 

Number I. 5th Edition. Canada Department of Energy, 

Mines and Resources, Ottawa, pp. 10-30. 
Bostock, H. H. 1970b. Physiographic regions of Canada. 

Geological Survey of Canada, Map 1254 A. Canada 



1978 



Cody and Talbot: Vascular Plants, NWT 



143 



Department of Energy, Mines and Resources, Ottawa. 
Cody, W. J. 1956. New plant records for northern Alberta 

and southern Mackenzie District, Northwest Territories. 

Canadian Field-Naturalist 74: 71-100. 
Cody, W. J. 1963. A contribution to the knowledge of the 

flora of southwestern Mackenzie District, N. W. T. 

Canadian Field-Naturalist 77: 108-123. 
Cody, W. J. 1978. Range extensions an'' -comments on the 

vascular flora of the continental No "st Territories. 

Canadian Field-Naturalist 92: 144-1 
Cody, W. J. and A. E. Porsild. 1968. Aduuions to the flora 

of Continental Northwest Territories, Canada. Canadian 

Field-Naturalist 82: 263-275. 
Cody, W.J. and S. S. Talbot. 1973. The pitcher plant, 

Sarracenia purpurea L. in the northwestern part of its 

range. Canadian Field-Naturalist 87: 318-320. 
Douglas, R. J. W. 1974. Trout River, District of Mac- 
kenzie. Geological Survey of Canada, Map 1371 A. 

Department of Energy. Mines and Resources, Ottawa, 

Ontario. 
Hamet-Ahti, L., T. Ahti, and T. Koponen. 1974. A scheme 

of vegetation zones for Japan and adjacent regions. 

Annales Botanici Fennici 11: 59-88. 
Harris, R. E. and A.'C. Calder. 1975. Climate of the 

Mackenzie Plain. Canada Department of Agriculture 

Publication 1554. 27 pp. 
Holdridge, L. R. 1967. Life zone ecology. Tropical Re- 
search Centre, San Jose, Costa Rica. 206 pp. 
Hooker, W. J. 1829-1840. Flora Boreali-Americana. 

Henry G. Bohn, London. 
Hulten, E. 1968. Flora of Alaska and neighboring terri- 
tories. Stanford University Press, Stanford. 1008 pp. 
Jeffrey, W. W. 1961. Notes on plant occurrence along 

lower Liard River, Northwest Territories. National 

Museum of Canada Bulletin 171: 32-1 15. 
Macoun, J. 1884. Catalogue of Canadian plants. Part H, 

Gamopetalae. Dawson Brothers, Montreal, pp. 193-394. 
Moss, E. H. 1953a. Forest communities in northwestern 

Alberta. Canadian Journal of Botany 31: 212-252. 
Moss, E. H. 1953b. Marsh and bog vegetation in north- 
western Alberta. Canadian Journal of Botany 31: 

448-470. 
Mulligan, G. A. 1972. Cytotaxonomic studies of Draba 

species in Canada and Alaska: D. oligosperma and D. 

incerta. Canadian Journal of Botany 50: 1763-1766. 



Porsild, A. E. 1943. Materials for a flora of the Con- 
tinental Northwest Territories of Canada. Sargentia 4: 
1-79. 

Porsild, A. E. 1951. Botany of southeastern Yukon adja- 
cent to the Canol Road. National Museum of Canada 
Bulletin 121: 1-400. 

Porsild, A. E. and W.J. Cody. 1968. Checklist of the 
vascular plants of Continental Northwest Territories. 
Plant Research Institute, Canada Agriculture, Ottawa. 
102 pp. 

Raup, H. M. 1935. Botanical investigations in Wood 
Buffalo Park. National Museum of Canada Bulletin 74: 
1-174. 

Raup, H. M. 1936. Phytogeographic studies in the Atha- 
basca - Great Slave Lake region. I. Catalogue of the 
vascular plants. Journal of the Arnold Arboretum 17: 
180-315. 

Raup, H. M. 1946. Phytogeographic studies in the Atha- 
basca - Great Slave Lake Region. II. Journal of the 
Arnold Arboretum 27: 1-85. 

Raup, H. M. 1947. The botany of southwestern Mac- 
kenzie. Sargentia 6: 1-275. 

Rowe, J. S. 1972. Forest regions of Canada. Environment 
Canada, Canadian Forestry Service, Publication Number 
1300. 171 pp. 

Scotter, G. W. 1966. A contribution to the flora of the 
eastern arm of Great Slave Lake, Northwest Territories. 
Canadian Field-Naturalist 80: 1-18. 

Scotter, G. W. and W.J. Cody. 1974. Vascular plants of 
Nahanni National Park and vicinity. Northwest Ter- 
ritories. Naturaliste Canadien 101: 861-891. 

Talbot, S. S. 1978. Vegetation of the Heart Lake area, 
Mackenzie District, N.W.T. Ph.D. thesis. Department 
of Botany, University of Alberta, Edm.onton. 

Thieret, J. W. 1961. New plant records for southwestern 
District of Mackenzie. Canadian Field-Naturalist 75: 
111-121. 

Thieret, J. W. 1963. Botanical survey along the Yellow- 
knife Highway, Northwest Territories, Canada. 1. Cata- 
logue of the flora. Sida 1: 1 17-170. 

Thieret, J. W. 1964. Botanical survey along the Yellow- 
knife Highway, Northwest Territories, Canada. II. 
Vegetation. Sida 1: 187-239. 

Received 4 October 1977 
Accepted 16 December 1977 



Range Extensions and Comments on the Vascular 
Flora of the Continental Northwest Territories 



William J. Cody 

Biosystematics Research Institute, Agriculture Canada, Ottawa, Ontario KIA 0C6 

Cody, William J. 1978. Range extensions and comments on the vascular flora of the continental Northwest Territories. 
Canadian Field-Naturalist 92(2): 144-150. 

Eighteen taxa, Poa abbreviata, Poajumifolia, Puccinellia agrostoidea, Puccinellia andersonnii, Carex arcta, Salix discolor, 
Rumex orbiculatus, Cerastium regelii, Stellaria umbellata, Draba lonchocarpa, Erucastnim gallicum, Leplarrhena 
pyrolifolia, Coelopleurum gmelinii, Polemonium acutiflorum f. lacteum, Castilleja yukonis, Orthocarpus luteus. Aster 
yukonensis, and Taraxacum pumilum are reported new to the flora of the continental Northwest Territories. Range 
extensions are reported for an additional 33 taxa. Notes are presented on six other taxa found in the area. 

Key Words: vascular plants. District of Keewatin, District of Mackenzie, Northwest Territories. 



There has been considerable botanical activity 
in the continental Northwest Territories (Figure 
1) since the publication of the checklist of the 
flora by Porsild and Cody (1968) and the 
supporting paper by Cody and Porsild (1968). 
Among the plant collections that have resulted 
from these activities, there have been a number 
of specimens that represent taxa new to the 
region, or range extensions within the region. 
Some of these have already been reported in the 
literature (Cody 1975; Cody and Talbot 1973, 
1978; Mulligan and Cody 1968; Mulligan and 
Porsild 1969; Nagy et al. (in press); Scotter and 
Cody 1974; and Wein et al. 1974). The present 
paper records 18 taxa that are new to the flora of 
the continental Northwest Territories, range 
extensions within the region for an additional 33 
taxa, and notes on six other taxa found in the 
region. Another paper (Cody et al., unpublished 
data) will treat additions to the flora of Nahanni 
National Park in the southern Mackenzie 
Mountains. 

In the text that follows, the abbreviations 
KEEW and MACK stand for District of 
Keewatin and District of Mackenzie respec- 
tively. 

Polypodiaceae 

Cryptogramma stelleri. MACK: in thick moist moss 
below falcon's nest, east end of Carcajou Lake, Mackenzie 
Mountains, 64°40'N, 127°52'W, Cody & Brigham 20943. 
This collection from the central eastern Mackenzie 
Mountains is the second for Mackenzie District and the 
species is thus newtoZone 1 ofPorsildand Cody( 1968). The 
only other collection is one by J. A. Calder from the 
Richardson Mountains W of the Mackenzie River Delta in 
Zone 2 (Cody and Porsild 1968). 



Cvstopteris montana. MACK: Richardson Mountains,' 
Summit Lake, I36°28'N, 67°42'W, Packer 1356 (DAO). 
Porsild and Cody (1968) recorded this species only from 
Zone 6. The collection cited above is the first record for Zone 
2, the Richardson Mountains, and is from the northernmost 
locality yet recorded in Canada. Here it would appear to be 
an expected range extension from sites in north-central 
Yukon Territory. Porsild and Cody (1968) inadvertently 
omitted reporting this species from Zone 1, whence it had 
been previously reported by Porsild (1945) and Raup (1947) 
on the basis of a collection by V. C. Wynne-Edwards from 
the north peak of Nahanni Mountain. 

Equisetaceae 

Equisetum fluviatile. MACK: Richardson Mountains, 
Canoe Lake, 68°13'N, 135°54'W, lakeshore, Cody & 
Johansson 12896 (DAO); same locality, Lambert s.n., Aug. 
1965 (DAO). This species was inadvertently omitted from 
Zone 2 by Porsild and Cody ( 1968). It is known in the same 
latitude from the Mackenzie River Delta. 

Alismaceae 

Sagittaria cuneata. MACK: Mackenzie River Delta, 
28 mi S of Inuvik, Lambert s.n., 5 Aug. 1966 (DAO). In the 
District of Mackenzie this species was hitherto known from 
the Slave River and about Great Slave Lake. This collection 
is an extension of range of some 1 126 km to the northwest. 
Elsewhere in the north it is known in southern Yukon and 
central Alaska. A distribution map is given in Hulten(1968). 

Gramineae 

Agrostis scabra. MACK: Mackenzie River Delta, 28 mi S 
of Inuvik, Lambert s.n., 5 Aug. 1966 (DAO). This collection 
represents a northwestward extension of the known range of 
some 435 km from Norman Wells (see Cody 1960, p. 78 for 
discussion). 

Poa abbreviata. MACK: rare, rocky north-facing slope on 
flattened parts where water stands for a short time. Cape 
Parry, 70°10'N, 124°43'W, Parmelee 2959 (D\0). This is a 
high-arctic, amphi-Atlantic species. It has not previously 
been reported from the arctic mainland of the District of 
Mackenzie. 



144 



1978 



CODY: Vascular Plants, NWT 



145 



BEAUFORT SEA 




YUKON 
TERRITORY 



Figure \. Map of the continental Northwest Territories showing floristic zones of Porsild and Cody (1968). 



Poa flexuosa. KEEW: Chesterfield, Beckett s.n., 25 Aug. 
1955 (CAN). This is an amphi-Atlantic species which is 
known in our area only on the basis of the collection cited 
above. 

Poa juncifolia. MACK: semi-wet meadow. Slave River 
Lowlands, northeastern Anne's Prairie near Hook Lake, 
60°46'N, 112°44'W, Reynolds 27 (DAO). This collection 
represents a northward extension of the known range from 
central Alberta. The species is new to the flora of the 
continental Northwest Territories and Zone 6 of Porsild and 
Cody (1968). 

Puccinellia agrostoidea. MACK: Mackenzie River Delta, 
northeastern shore of Richards Island, Cody & Ferguson 
10162, 10199; Toker Point, Cody & Ferguson 10272; 
Anderson River Delta, Barry 464; Nicholson Peninsula, 
Parmelee 2542; Cape Parry, Parmelee 2974; Clinton Point, 
Parmelee 3213 (all DAO). This species was described on the 
basis of material from Banks Island. The range is now 
extended to the Arctic Coast of the District of Mackenzie. It 
is a non-littoral species of turfy places in tundra. 

Puccinellia andersonii. MACK: Mackenzie River Delta, 
Richards Island, Morrison s.n. July 1966 (DAO); sandy soil 
above ocean cliffs, Tuktoyaktuk Peninsula, 70°02'N, 
129°29'W, Larsen & Owen 4242 {DAO). This is a high-arctic 
species known from East Greenland to Banks Island and 



widely disjunct to the Mackenzie Delta and Point Lay, 
Alaska (type locality). It is new to the flora of mainland 
Canada. 

Vahlodea atropwpurea ssp. atropurpurea. MACK: in 
moss among stones along lakeshore and in moist depression 
on esker. Lynx Lake, 62°20'N, 106°25'W, Cody 15375. _ 
15387, 15389 (DAO); stony lakeshore, Mantic Lake, 
62°18'N, 104°25'W, Cody 15474, 15475 (DAO). KEEW: 
gravelly lakeshore, Baralzon Lake, 60°00'N. 98°10'W, 
Scoggan and Baldwin 8363 (CAN). The collections cited here 
are the basis for the report of the presence of this subspecies 
in eastern continental Northwest Territories. Vahlodea 
atropurpurea s.l. is circumpolar; in western North America it 
is represented by ssp. latifolia. 

Cyperaceae 

Carex arcta. MACK: swampy area, Hjalmer Lake, 
61°05'N, 109°15'W, Scotter 3021. This is a boreal North 
American species which occurs from Labrador to Alaska. It 
is new to the flora of the District of Mackenzie. 

Carex concinna. KEEW: at base of ledge of rocks in sparse 
spruce timber, northwestern extremity of Nueltin Lake, 
Harper 2399 (CAN). This species, which is common in 
western District of Mackenzie, is apparently rare in the 
District of Keewatin where it is known only from the 
collection cited above. 



146 



The Canadian Field-Naturalist 



Vol. 92 



Carex loliacea. MACK: Mackenzie River Delta, 28 mi S of 
Inuvik, Lambert s.n., 3 Aug. 1966 (DAO). This is a rare plant 
even in the southern parts of the District of Mackenzie. The 
collection cited here represents a northwestward extension of 
the known range of some 724 km from the southern part of 
the Mackenzie Mountains. 

Carex macloviana. MACK: in pure sand of dunes. 
Sawmill Bay, Great Bear Lake, Shacklette 3068 (CAN); 
fertile grassy slopes and herb mats, eastern slope of 
Mackenzie Mountains, W of Mackenzie River Delta, 
Porsild 6759 (CAN); Keith Arm. Russell Bay, Great Bear 
Lake,65°28'N, \21°55'V^ , Porsild s.n., 2% \ug. 1928 (CAN); 
Etacho Point, Great Bear Lake, 66°0'N, 121°30'W, Porsild 
s.n.. 24 Aug. 1928 (CAN). Porsild and Cody ( 1968) neglected 
to indicate the zones in which this sedge was known to them. 
From Zone 1 (the western parts of the Mackenzie Mountains 
adjacent to the Yukon border), and Zone 6 (Mackenzie River 
between Blackwater River and Norman) it had been 
previously reported by Raup (1947). The specimens cited 
above indicate its presence in zones 2 and 5. 

Carex sartwellii. MACK: rare along tractor trail through 
sedge-grass meadow W of Le Grand Detour, Slave River, 
60°21'N, 1 I2°44'W. Cody 13947 (DAO); rare in wet sedge 
meadow, 3 mi N from northeastern loop of Le Grand 
Detour, Slave River, 60°24'N, 112°27'W, Cody 14012 
(DAO); sedge -grass meadow near Hook Lake, 3 mi E of 
Slave River, 60°43'N, 112°50'W, Cody 14093 (DAO). The 
only other collections thus far recorded from the District of 
Mackenzie are those of Thieret from along the Mackenzie 
Highway (Thieret 1961). South of our area, the nearest 
known locality is Peace Point in southern Wood Buffalo 
Park, Alberta (Raup 1935). 

Carex sychnocephala. MACK: Slave River Lowland, 
Sawmill Island, Grant 1702 (DAO). This is the third 
collection thus far recorded for the district; other collections 
are from Lower Hay River and Yellowknife. Carex 
sychnocephala is a boreal North American species which 
occurs in Canada from southwest Quebec to the interior of 
British Columbia, southeastern Yukon Territory and eastern 
Alaska. To the south of our area this plant is known from 
central Wood Buffalo Park and on the shores of Lake 
Athabaska (Raup 1936). 

Eriophorum viridi-carinatum. MACK: hot spring site, 
Mackenzie Mountains, Backbone Range, Twitya River, 
63°56'N. I29°20'W, Cody and Scotter 19579 (DAO). This 
species was previously known in the District of Mackenzie 
from a few collections about Great Slave Lake (Raup 1936; 
Thieret 1961). It is also known from the extreme southeast 
corner of the Yukon Territory. It is new to Zone 1 of Porsild 
and Cody (1968). In Canada E. viridi-carinatum is found 
from Newfoundland to British Columbia in rich bogs and 
peaty meadows. 

Scirpus rollandii. MACK: hot spring site, Mackenzie 
Mountains, Backbone Range, Twitya River, 63°56'N, 
129°20'W, Cody and Scotter 19563 (DAO). Previously 
known in the District of Mackenzie from a single collection 
on the Yellowknife Highway north of Great Slave Lake 
(Thieret 1962). Ne\y to Zone 1 of Porsild and Cody (1968). 

Scirpus rufus var. neogaeus. MACK: forming dense 
stands on shallow silty soil over stones in broad river valley. 



Keele River at "Caribou Flats," Mackenzie Mountains, 
63°45'N, 127°54'W, Cody 20018, Cody and Brigham 20652 B 
(DAO). This is not a common plant in North America. 
Fernald (1951) gives the following information, "Saline or 
brackish marshes, rarely in fresh peal, Nfld. to lower St. 
Lawrence R., Que., s. along coast to sw. N.S. and sw. N.B., 
shores of Hudson B., Man." In the herbarium of the 
Biosystematics Research Institute there are also several 
collections from Sutherland (now part of Saskatoon) in 
south-central Saskatchewan. This is some 724 km southwest 
of the collection from the Mackenzie Mountains. Hulten 

(1967) sub Blysmus rufus. repeats an earlier report by J. P. 
Anderson of a collection from Matanuska in Alaska, but no 
indication is given as to whether this should be referred to 
var. rufus or var. neogaeus. The Matanuska locality is 
423 km W of the site reported above. Scirpus rufus is also 
known in the District of Mackenzie from near Wrigley on the 
Mackenzie River. The species is new to Zone 1 of Porsild and 
Cody (1968). 

Salicaceae 

Salix arctophila. MACK: Mackenzie Mountains: mead- 
ow by slough, Keele River 64°12'N, 127°25'W, Cody and 
Scotter 19263 (DAO); hot spring meadow, Twitya River, 
64°08'N, 128°27'W, Cody and Scotter 19457 (DAO); wet 
shallow soil over stones in broad river valley. Keele River at 
"Caribou Flats," 63°45'N, 127°54'W. Cody 20034 (DAO): 
Sphagnum fuscum island in sedge fen about 1 mi NE of 
Mile 80, Mackenzie Highway, 60°52'N, 116°36'W, Talbot 
3752 (DAO); seismic line, about 0.7 mi N of Mile 86, 
Mackenzie Highway, 60°52'N, 116°45'W, Talbot 2206 
(DAO); open Picea mariana. Larix laricina woods on marl 
deposit, 46 mi N of Fort Providence Junction on 
Yellowknife Highway, 61°47'N, 116°46'W, Argus and 
Chunys 7948: low hummock in slough, small unnamed lake 
on S side of Horn Plateau, 61°59'N, 1 19°22'W, Cody 18584 
(DAO). This is an eastern arctic species which extends 
westward to the Mackenzie and Richardson Mountains, and 
the Arctic Coast of the Yukon Territory. Porsild and Cody 

(1968) recorded it in their Zones 3, 4, and 5; the specimens 
cited above indicate its presence in Zones 1 and 6 as well. 

Salix Candida. MACK: Mackenzie Mountains: in shallow 
silty soil over stones in broad river valley, Keele River at 
"Caribou Flats," 63°45'N, 127°54'W, Cody 20025 (12) AO)\ 
hot spring meadow by Twitya River, 64°08'N, 128^27'W, 
Cody 19996. Cody and Scotter 19492 (DAO); spring flood 
terrace, Keele River, 64° I2'N, 127°25'W, Cody and Scotter 
19241 (DAO); hot spring site, Twitya River. 63°56'N, 
129°20'W. Cody and Scotter 19560 (DAO). Salix Candida 
has been recorded from the Mackenzie Mountains. Zone 1 of 
Porsild and Cody (1968) only once. This was from the South 
Nahanni River system (Scotter and Cody 1974). The sites 
listed above are all from the Keele River drainage system. 

Salix discolor. MACK: border of cleared ground by 
airstrip. Fort Simpson, Cody and Matte 8133 (DAO); Mile 
77 Mackenzie Highway, 60°48'N. 1 16°37'W. Talbot 2174 
(CAN); Mackenzie River. Richardson, Franklin Expedition 
(CAN) (all det Argus). The early Richardson specimen has 
gone unreported until this time and may have been ignored 
because there were no recently collected specimens to 
support it. Salix discolor is a boreal North American species 
which is found in Canada from Newfoundland to western 



1978 



CODY: Vascular Plants, NWT 



147 



Alberta. The specimens cited above are disjunct up to 
805 km from known localities in central Alberta. 

Polygonaceae 

Koenigia islandica. MACK: Richardson Mountains, 
common along west bank of Little Bell River near Summit 
Lake, 67°42'N, 136°28'W, Packer 1575 (DAO). This is a 
circumpolar species with numerous disjunct populations. It 
has been collected only a few times in our area but has 
perhaps been overlooked. New to Zone 2 of Porsild and 
Cody (1968). 

Rumex orbiculatus. MACK: Buffalo Lake, 60°08'N, 
115°53'W, Ducruc 194.1 {Q¥ A. Photo DAO). This is a range 
extension northward from central Alberta. It is new to the 
flora of the District of Mackenzie and Zone 6 of the Porsild 
and Cody (1968). 

Caryophyllaceae 

Cerastium regelii. MACK: mossy moist soil near 
lakeshore, Tuktoyaktuk Peninsula, 70°02'N, 129°29'W, 
Owen and Larsen 74-4227 (DAO). This is a circumpolar 
species which is common in some parts of the Canadian 
Arctic Archipelago. From the Canadian mainland it is 
known only from Melville Peninsula and the present 
collection. New to Zone 3 of Porsild and Cody (1968). 

Gvpsophila paniculata. MACK: persisting and spreading 
after cultivation. Fort Smith, Cody 19117 (DAO). This 
native of Eurasia is widely cultivated as a herbaceous 
ornamental. It has escaped in various parts of Canada, and 
large infestations can be found in the southern parts of 
Saskatchewan, Alberta, and British Columbia (Darwent 
1975). 

Minuartia macrocarpa. This species was inadvertently 
reported by Porsild and Cody (1968) from Zone 2 rather than 
Zone 1, whence it is known from several collections (Raup 
1 947). Porsild ( 1 943) has reported M. macrocarpa from King 
Point on the Arctic Coast of the Yukon Territory, near the 
District of Mackenzie border. 

Stellaria umbellata. MACK: sheltered wet bank. Canoe 
Lake, Richardson Mountains, 68° 13'N, 135°47'W, Lambert 
s.n., 8 Aug. 1966 (DAO). This is an amphi-Beringian species 
which is disjunct from central Yukon to the locality cited 
above, the mountains of southwestern Alberta, Nevada, and 
Oregon. New to the flora of continental Northwest 
Territories. 

Ranunculaceae 

Ranunculus cymbalaria var. cymbalaria. MACK: Mac- 
kenzie Mountains: along river shore below salt lick, Keele 
River "Slew Lick" 64°13'N, !27°55'W, Cody and Scotter 
19176: in shallow silty soil over stones in broad river valley, 
Keele River at "Caribou Flats," 63°45'N, 127°54'W, Cody 
20020; steep moist stony waterway below hot spring 
meadow, by Twitya River about 2 mi W of Deca Creek, 
64°08'N, 128°27'W, Cody 19987. It would ap)pear that, at 
least in this part of its range, R. cymbalaria requires a more 
or less saline habitat. It has been known from the lowland 
adjacent to the Mackenzie River as far north as Norman 
Wells (Cody 1960) but is new to the flora of the Mackenzie 
Mountains (Zone 1 of Porsild and Cody 1968). All three 
collections cited above are from the Keele River drainage. 



Cruciferae 

Cardamine microphylla; C. minuta. MACK: Mackenzie 
Mountains: shattered limestone slope, alt. 5500 ft, "Coral 
Peaks," 65°06'N, 129°10'W, Cody and Scotter 19599; among 
rocks on alpine slope, alt. 5200 ft, "Coral Peaks", 65=03?^, 
128°57'W, Cody and Scotter 19636. This is an amphi- 
Beringian species which is rare in northern Alaska, unknown 
in the Yukon Territory, but has been recorded from the 
southern Richardson Mountains near the Yukon border in 
northwestern District of Mackenzie (Cody and Porsild 
1968). The specimens cited above again extend the known 
range of this rare Canadian plant into the Carcajou Range of 
the Mackenzie Mountains. This isadistance of some433 km 
SE of the previously known Mackenzie District collections. 
The species is new to Zone I of Porsild and Cody (1968). 

Draba lonchocarpa. MACK: Mackenzie Mountains: 
Sekwi Range: mountains on north side of June Lake, 
63°3rN, 128°40'W, 5000-5500 ft, crevice in limestone rock 
face, Cody 17239. Draba lonchocarpa is a Cordilleran 
species which barely enters Yukon and Alaska. The one 
locality cited by Porsild (1951) in the Yukon Territory was 
from Rose-Lapie Pass, Mile 1 18 Canol Road. It is new to the 
District of Mackenzie and the continental Northwest 
Territories. 

Erucastrwn gallicum. MACK: Roadside, Fisherman 
Lake, 60°20'N, 123°47'W, 8 Sept. 1974, Lamont 662 (Sask, 
fragment DAO); road-cut near Poplar River, 6I°I3'N, 
121°19'W, 9 Sept. 1974, Scotter 22817 (DAO). This is an 
introduced weed which is apparently spreading quickly 
across Canada. According to Franktonand Mulligan (1970) 
it first arrived in North America in 1903 and was first found 
in Canada at Emerson, Manitoba in 1922. New to the flora of 
the continental Northwest Territories. 
Lesquerella calderi. MACK: locally common on wet and 
rubbly limestone flats and slopes about 5 mi N of Home 
Lake, Richardson Mountains, 67°49'N, 135°59'W, alt. 
2000 ft. Colder 33936 (DAO). Lesquerella calderi is endemic 
to the Ogilvie Mountains of central Yukon Territory and the 
east and west slopes of the Richardson Mountains. The 
specimen cited here is the only collection thus far known 
from the District of Mackenzie (Mulligan and Porsild 1969). 

Saxifragaceae 

Leptarrhena pyrolifolia. MACK: Cirque Lake, 63° 17.57*1, 
130°08'W, alt. 5000-6000 ft, lower slopes by lake, Cody and 
Brigham 20608 (DAO). New to the District of Mackenzie. 
Porsild (1951) recorded this Cordilleran-Pacific Coast 
species as new to the Yukon Territory. A distribution map 
which includes the Yukon sites is given by Hulten (1968). 
Because this species occurred so close to the Yukon- 
Mackenzie border at the northwest end of the Itsi Range 
adjacent to the Canol Road, Porsild and Cody (1968) 
suggested that it might be f-ound as well in the District of 
Mackenzie. 

Leguminosae 

Astragalus americanus. MACK: in deep moss in Picea 
glauca vjoods. Mackenzie Mountains, Keele River. 64° 12'N, 
127°25'W,alt. 1400 ft, Cody atid Scotter 19283 (DAO). This 
is only the second record for this species from the Mackenzie 
Mountains. Scotter and Cody (1974) recorded it from the 
South Nahanni River drainage. Along the Mackenzie River, 



148 



The Canadian Field-Naturalist 



Vol. 92 



A. americanus is known only as far north as Norman Wells at 
65°17'N. 

Oxytropis nigrescens ssp. bryophylla. MACK: east-facing 
slope, shallow soil on rocky hilltop. Canoe Lake, Richardson 
Mountains, 68°13'N, 135°54'W, Cody 12962 (DAO); 
sparsely-vegetated shale slope, Richardson Mountains, 
67°33'N, 136°12'W, CaWer i^077 (DAO); finely-weathered 
sandstone outcrops. Home Lake, Richardson Mountains, 
67°45'N, 136°0rW, Calder 33876 (DAO); limestone 
mountainsides, June Lake, 63°30'N, 128°40'W, Mackenzie 
Mountains, Cody 17155, 17439, 17454 (DAO); moist turf 
over limestone on mountain slope, "Banana" Lake, 63°49'N, 
127°28'W, Backbone Range, Mackenzie Mountains, Cody 
17502 (DAO). This subspecies is found in many places in 
Alaska, but in the Yukon and Mackenzie and Richardson 
Mountains of the District of Mackenzie, it is apparently of 
rare occurrence. 

Onagraceae 

Epilobium arclicum. MACK: sparingly in wet moss in alpine 
tundra, eastern slope of Richardson Mountains, appro.xi- 
mately 68° N, 136'W, Porsild 6842 (CAN). This specimen 
was reported from the Richardson Mountains by Porsild 
(1943), but in error the species was not reported by Porsild 
and Cody (1968) for Zone 2. The other collection (6704) cited 
by Porsild (1943) sub E. arcticum is E. anagallidifolium. 

Umbelliferae 

Coelopleurum gmelinii; Angelica lucida sensu Hulten 1968. 
MACK: shrubby alpine tundra, center peak. Pointed 
Mountain, 60°22'N, 123°55'W, Lamont 308 (DAO). The 
map in Hulten ( 1968) shows this species as being essentially 
coastal, but with an inland population apparently following 
the west-flowing rivers into central Alaska, and a disjunct 
location at the northwest end of the Itsi Range adjacent to 
the Canol Road (Porsild 1951) in eastern Yukon Territory. 
The collection cited above represents another disjunct 
location and the species is new to the District of Mackenzie 
and Zone 1 of Porsild and Cody (1968). 

Ericaceae 

Kalmia polifolia. MACK: Mackenzie Mountains, Mile 216 
Canol Road, near the Yukon border, 63°2rN, 129°42'W, 
alt. 5000 ft, Cody 19973 (DAO). A single plant was 
discovered in a Betula glandulosa - Salix community, a 
habitat totally unlike the wet Sphagnum conditions in which 
K. polifolia grows in the eastern District of Mackenzie. This 
species is new to Zone 1 of Porsild and Cody (1968), although 
Porsild (1945) had collected it at Macmillan Pass in nearby 
Yukon Territory. 

Vaccinium quadhpetalus. MACK: base of Sphagnum 
fuscum hummocks, peat plateau 6.4 km N by NNW of Fort 
Simpson, 61°54'N, 121°20'W, Walker 2023 (DAO). Pre- 
viously known in the District of Mackenzie from only two 
localities, Norman Wells and Liard River near Fort Liard 
(Cody 1960; Jeffrey 1961). 

Gentianaceae 

Gentiana affinis. MACK: Mackenzie Mountain?, in turf 
over stones in broad river valley among low Betula 



glandulosa, Keele River at "Caribou Flats," 63°45'N, 
127°54'W, Cody 20054 (DAO); cleared low river terrace, 
Keele River at Canadian Wildlife Service Camp, 64° 12'/2'N, 
127°25'W, Cody 18953 (DAO). Cody and Porsild (1968) 
recorded G. affinis as new to the District of Mackenzie on the 
basis of a specimen collected somewhere along the Keele 
River and another older but hitherto unnoticed specimen in 
the Lawson Herbarium from Fort Good Hope on the 
Mackenzie River. This was an extension of the known range 
of the species of some 2575 km N from the otherwise known 
northern limit near the North Saskatchewan River. The 
present collections with more exact locality data confirm the 
distribution along the Keele River in the Mackenzie 
Mountains. Another recent collection from Mile 180 
Mackenzie Highway has been reported by Cody and Talbot 
(1978). 

Gentiana raupii. MACK: Mackenzie Mountains, hummock 
by hot spring, Twitya River about 2 mi W of Deca Creek, 
64°08'N, 128°27'W, alt. 2300-2700 ft, Cody and Scotter 
19482 (DAO). Gentiana raupii until now was known only 
from the lowlands of the Mackenzie and Liard Rivers and 
about western Great Slave and Great Bear Lakes. The 
present collection at a hot spring site extends the known 
range into Zone 1 of Porsild and Cody (1968) at an altitude 
considerably above that of the Mackenzie River. 

Polemoniaceae 

Polemonium acutiflorwn f. lacteum. MACK: Mackenzie 
Mountains, near junction of Keele and Natla River, 
approximately 63°35'N, 127°55'W, Semeniuk, s.n.. 15 July 
1972 (DAO). This white-flowered form has been noted from 
several places in the Yukon Territory and Alaska (Hulten 
1948; Lepage 1950), but it has not previously been recorded 
from the District of Mackenzie. 

Castilleja vukonis. MACK: grassy slopes. Seagull Cliff, 
Campbell Lake, 68°08'N, 133°20'W, Porsild 2010 (CAN); 
Picea glauca woods and muskegs, Husky River, Mackenzie 
River Delta, about 68° N, 135°30'W, Bryant 6623 (CAN). 
This is an endemic of northwestern North America which 
was previously known from central and southwestern Yukon 
and southeastern Alaska. It is new to the continental 
Northwest Territories and Zone 3 of Porsild and Cody 
(1968). 

Lagotis stelleri. MACK: Mackenzie Mountains, Mile 216 
Canol Road near headwaters of Tischu River, 63°22'N, 
129°42'W, Cody and Scotter 19294, Cody 19949 (DAO). 
Lagotis stelleri has previously been collected in the District 
of Mackenzie only from the Richardson Mountains (Porsild 
1943). The present collections extend the known range from 
the Yukon into Zone 1 of Porsild and Cody ( 1968). At this 
site the species was frequent in moist hummocky tundra 
slopes. 

Orthocarpus luteus. ALTA.: bank of the Salt River, 14 mi W 
of Fort Smith (2 mi S of Northwest Territories - Alberta 
border), 59°58'N, 112°23'W, Cody and Brigham 21075 
(DAO). MACK: dry meadow at edge of white spruce forest, 
Slave River lowlands. Hook Lake campsite, 60°43'N, 
112°47'W, Reynolds 214, 244 (DAO). These collections 
represent a northward extension of the known range from 
Peace Point in the southern part of Wood Buffalo Park 



1978 



CODY: Vascular Plants, NWT 



149 



(Raup 1936). It is new to the flora of continental Northwest 
Territories and Zone 6 of Porsild and Cody (1968). 

Plantaginaceae 

Plantago eriopoda. MACK: Mackenzie Mountains, hot 
springs meadow by Twitya River, 64°08'N, 128°27'W, Cody 
and Scatter 19455 ( DAO): steep moist stony waterway below 
hot spring meadow, same locality, Cody 19986a (DAO). 
Bassett (1973) presented a map of the North American 
distribution of this species but omitted locations from the 
Arctic Coast E of the Mackenzie River Delta cited by Porsild 
(1943). Along the Mackenzie River valley it is also known 
from the mouth of the Keele River (L/>7(iiflri25(CAN))and 
between Norman Wells and the mountain, 65°17'N, 
126°50'W (Rigby 3 (CAN)). It is new to Zone 1 of Porsild 
and Cody (1968). 

Plantago canescens: P. septata. MACK: Mackenzie Moun- 
tains, in crevices of rock, steep north bank of river, Keele 
River, 64° 13 'N, I27°32'W, Cody and Scatter 19204 (DAO): 
steep moist stony waterway below hot spring meadow by 
Twitya River, 64°08'N, I28°27'W, Cody 19986b (DAO). 
Plantago canescens is frequent along the shores of the 
Mackenzie River: the collections cited here extend the 
known range into Zone 1 of Porsild and Cody (1968). 

Compositae 

Artemisia borealis. MACK: Mackenzie Mountains, steep 
moist stony waterway below hot spring meadow by Twitya 
River, 64°08'N, 128°27'W, Cody 19991 (DAO). This is a 
circumpolar subarctic species which has previously been 
recorded from Zones 3,4, and 5 of Porsild and Cody (1968). 
It is new to Zone !, the Mackenzie Mountains. 

Artemisia canadensis. MACK: Mackenzie Mountains, steep 
eroding bank of Keele River, 64° 13'N, 127°27'W, Cody and 
Scatter 19372 (DAO). Artemisia canadensis is a lowland 
species which has not previously been recorded from Zone 1 
of Porsild and Cody (1968). 

Artemisia frigida. MACK: Mackenzie Mountains, steep 
slope and rocky face overlooking river, Keele River, 
64°13'N, 127°55'W, Cody and Scatter 19190 (DAO): steep 
eroding bank of river, Keele River, 64°13'N, 127°27"W, 
Cody and Scatter 19380 (DAO). Artemisia frigida was 
recorded as new to Zone 1 of Porsild and Cody (1968) on the 
basis of collections from the South Nahanni River drainage. 
The collections cited here extend the range into the Keele 
River drainage in the Mackenzie Mountains. 

Aster alpinus ssp. vierhapperi. MACK: heathy area on 
limestone knoll above lake. Home Lake, Richardson 
Mountains, 67°45'N, 136°0rW, CaWe/-ii9/2 (DAO): steep 
grassy slope underlain by limestone, 3 mi N of Home Lake, 
Richardson Mountains, Calder 33941 (DAO). These collec- 
tions are a part of the population in the northern Yukon 
reported by Wein et al. ( 1 974). In the Yukon this taxon is not 
otherwise known from north of latitude 63°N, and in the 
District of Mackenzie from north of the central Mackenzie 
Mountains and Great Bear Lake (Raup 1947). It is new to 
Zone 2 of Porsild and Cody (1968). 

Aster yukonensis. MACK: Mackenzie Mountains, steep 
moist stony waterway below hot spring meadow, Twitya 
River about 2 mi W of Deca Creek, 64°08'N, 128°27'W, alt. 



2300-2700 ft, Cody 19988 (DAO): hot spring meadow, same 
locality, Cody and Scatter 19451 (DAO): in shallow silty soil 
over stones in broad river valley, Keele River at "Caribou 
Flats," 63°45'N, 127°54'W, alt. 2500 ft, Cody 20023. Cody 
and Brigham 20654 (DAO): west flank of Norman Range: 
dry frost hummocks near stream, open. Fish Lake (Hodge- 
son Lake), 5 mi NE of Norman Wells, 65° 17.5'N, 126°38'W, 
alt. 600 ft, Shewell 133 (DAO). The map in Hulten (1968) 
indicates collections only from the type region near Kluane 
Lake in southwest Yukon and from just W of 150° near the 
Arctic Circle in northern Alaska. The known range of this 
endemic species is now extended E across the Mackenzie 
Mountains to the west flank of the Norman Range E of the 
Mackenzie River. This species apparently has an affinity for 
saline situations. At "Caribou Flats" it shares a most 
interesting situation with such plants as Gentiana affinis, 
which is disjunct 2575 km from its main range S of the North 
Saskatchewan River (Cody and Porsild 1968), and Scirpus 
rufus, a circumpolar species which in North America is 
known from a single locality in Alaska, and Saskatchewan, 
about James Bay, and in the east, about the lower St. 
Lawrence River, Newfoundland, and the Maritime Prov- 
inces. Aster yukonensis is somewhat similar to A. pygmaeus, 
an endemic species found in northern District of Mackenzie 
and on the southern parts of Banks and Victoria Islands 
in the Arctic Archipelago. Aster yukonensis may be 
distinguished from A. sibiricus by its purplish pappus, a 
dense coating of fine glandular hairs among the flattened 
longer multicellular hairs on the tegules, the upper stem and 
upper leaves, and the generally more thinly distributed white 
hairs. 

Crepis elegans. MACK: Mackenzie Mountains, gravel bar 
of river, Keele River, 64°12'N, 127°25'W, Cody and Scatter 
19386 (DAO): steep gravelly bank of river below hot spring 
area, Twitya River, 64°08'N, 128°27'W, Co<3'.r /99S2(DAO). 
This species has its northernmost known distribution in 
the District of Mackenzie along the Carcajou River W of 
Norman Wells (Cody 1960). The specimens cited here are 
from near the same latitude but are the first from this latitude 
in the Mackenzie Mountains. Scotter and Cody (1974) have 
recently recorded C. elegans from the south Nahanni River 
drainage as new to Zone 1 of Porsild and Cody (1968). 

Erigeron grandiflarus Hook. ssp. arcticus. MACK: Mac- 
kenzie Mountains, Little Carcajou Lake, 64°33'N, 
128°23'W, 4000 ft, Stelfox s.n., 13 July 1972 (DAO): mesic 
alpine tundra, north ridge of Pointed Mountain, 60°27'N, 
123°52'W, Lamont FL 373 (SASK, fragment DAO). The 
status and known distribution of this subspecies are 
discussed by Porsild (1955, 1974). It is new to Zone 1 of 
Porsild and Cody (1968). 

Petasites palmatus. MACK: Mackenzie Mountains, steep 
eroding till slope overlooking river, Keele River, 64°13'N, 
127°10'W, CadyandScatterl9369(DAO). nt\N\.oZonQ\ of 
Porsild and Cody (1968). Petasites palmatus was already 
known from Zones 5 and 6. 

Taraxacum pumilum. MACK: Nicholson Island, Anderson 
River, Porsild 16782 (CAN): open clay spots in upland 
tundra 60 mi E of Tuktoyaktok, Eskimo Lake Basin, 
Porsild 16773 (CAN). This is a high-arctic species here 
reported for the first time from the mainland. 



150 



The Canadian Field-Naturalist 



Vol. 92 



Literature Cited 

Bassett, I. J. 1973. The Plantains of Canada. Canada 
Department of Agriculture, Research Branch Monograph 
7: 1-46. 

Cody, W. J. 1960. Plants of the vicinity of Norman Wells, 
Mackenzie District, Northwest Territories. Canadian 
Field-Naturalist 74: 71-100. 

Cody, W. J. 1975. Scheuchzeria palustris L. (Scheuch- 
zeriaceae) in northwestern North America. Canadian 
Field-Naturalist 89: 69-71. 

Cody, W. J.and A. E. Porsild. 1968. Additions to the flora 
of Continental Northwest Territories, Canada. Canadian 
Field-Naturalist 82: 263-275. 

Cody, W.J. and S. S. Talbot. 1973. The Pitcher Plant, 
Sarracenia purpurea L. in the northwestern part of its 
range. Canadian Field-Naturalist 87: 318-320. 

Cody, W. J. and S. S. Talbot. 1978. Vascular plant range 
extensions to the Heart Lake area. District of Mackenzie, 
Northwest Territories. Canadian Field-Naturalist 92(2): 
137-143. 

Darwent, A. L. 1975. The biology of Canadian weeds. 14. 
Gvpsophila paniculata L. Canadian Journal of Plant 
Science 55: 1049-1058. 

Fernald, M. L. 1951. Gray's manual of botany. 8th Edition. 
American Book Co., New York. 1632 pp. 

Frankton, C. and G. A. Mulligan. 1970. Weeds of Canada. 
Canada Department of Agriculture Publication 948. 
217 pp. 

Hulten, E. 1948. Flora of Alaska and Yukon. VIII. Lunds 
Universitets Arsskrift, Neue Folge44(l): 1203-1341. 

Hulten, E. 1967. Comments on the flora of Alaska and 
Yukon. Arkiv for Botanik 7(1): 1-147. 

Hulten, E. 1968. Flora of Alaska and neighboring ter- 
ritories. Stanford University Press. Stanford. 1008 pp. 

Jeffrey, W. W. 1961. Notes on plant occurrence along 
Lower Liard River, N.W.T. National Museum of Canada 
Bulletin 171: 32-115. 

Lepage, E. 1950. Variations mineures de quelques plantes 
du nord-est du Canada et de I'Alaska. Naturaliste 
Canadien 77: 228-231, 

Mulligan, G. A. and W.J. Cody. 1968. Draba norvegica, 
disjunct to the Mackenzie District, Northwest Ter- 
ritories, Canada. Canadian Journal of Botany 46: 
1334-1335. 

Mulligan, G. A. and A. E. Porsild. 1969. A new species of 
Lesquerella (Cruciferae) in northwestern Canada. Cana- 
dian Journal of Botany 47: 215-216. 



Nagy, J. A., A. M. Pearson, B. C. Goski, and W. J. Cody. 

1978. Range extensions of vascular plants in northern 
Yukon Territory and northwestern District of Mackenzie. 
Canadian Field-Naturalist. 

Porsild, A. E. 1943. Materials for a flora of the Continental 
Northwest Territories of Canada. Sargentia 4: 1-79. 

Porsild, A. E. 1945. The alpine flora of the east slope of 
Mackenzie Mountains, Northwest Territories. National 
Museum of Canada Bulletin 101: 1-35. 

Porsild, A. E. 1951. Botany of southeastern Yukon ad- 
jacent to the Canol Road. National Museum of Canada 
Bulletin 121: 1-400. 

Porsild, A. E. 1955. The vascular plants of the western 
Canadian Arctic Archipelago. National Museum of 
Canada Bulletin 135: 1-226. 

Porsild, A. E. 1974. Materials for a flora of central Yukon 
Territory. National Museums of Canada Publications in 
Botany 4: 1-77. 

Porsild, A. E. and W. J. Cody. 1968. Checklist of the 
vascular plants of Continental Northwest Territories. 
Plant Research Institute, Canada Agriculture, Ottawa. 
102 pp. 

Raup, H. M. 1935. Botanical investigations in Wood Buf- 
falo Park. National Museum of Canada Bulletin 74: 
1-174. 

Raup, H. M. 1936. Phytogeographic studies in the Atha- 
baska-Great Slave Lake region. Journal of the Arnold 
Arboretum 17: 180-315. 

Raup, H. M. 1947. The botany of southwestern Mac- 
kenzie. Sargentia 6: 1-275. 

Scotter, G. W. and W. J. Cody. 1974. Vascular plants of 
Nahanni National Park and vicinity. Northwest Terri- 
tories. Naturaliste Canadien 101: 861-891. 

Thieret, J. W. 1961. New plant records for southwestern 
District of Mackenzie. Canadian Field-Naturalist 75: 
111-121. 

Thieret, J. W. 1962. New plant records from the District 
of Mackenzie, Northwest Territories. Canadian Field- 
Naturalist 76: 206-208. 

Wein, R. W., L. R. Hettinger, A. J. Janz, and W. J. Cody. 
1974. Vascular plant range extensions in the northern 
Yukon Territory and northwestern Mackenzie District, 
Canada. Canadian Field-NaturaUst 88: 57-66. 



Received 4 October 1977 
Accepted 16 December 1977 



Seasonal Food Habits of the Barn Owl (Tyto alba) 
on the Alaksen National Wildlife Area, 
British Columbia 

Neil K. Dawe,' Craig S. Runyan,2 and Richard McKelvey3 

'Canadian Wildlife Service, R.R. 1, Qualicum Beach, British Columbia VOR 2T0 

25080 45th Avenue, Delta, British Columbia V4K 1K3 

^Canadian Wildlife Service, 5421 Robertson Road, Delta, British Columbia V4K 3N2 

Dawe, Neil K., Craig S. Runyan, and Richard McKelvey. 1978. Seasonal food habits of the Barn Owl {Tyto alba) on the 
Alaksen National Wildlife Area, British Columbia. Canadian Field-Naturalist 92(2): 151-155. 

A study of Barn Owl (Tyro alba) food habits on the Alaksen National Wildlife Area, British Columbia, was conducted 
through pellet analysis from September 1974 to December 1975. From 497 pellets, 1156 individual prey animals were 
recovered including six species of mammals, nine species of birds, insects, fish, and a crustacean. Microtus townsendiiwas the 
most important prey item in the owl's diet contributing 85.4% of the total mammalian-prey biomass. It was followed by 
Rattus sp. (12.1%) and Sorex vagrans (1.9%). The number of animals per pellet averaged 2.33 over the study period. 

Key Words: Tyto alba. Barn Owl, food habits, British Columbia. 



In western Canada the Barn Owl ( Tyto alba) is 
resident only in extreme southwestern British 
Columbia (Godfrey 1966). Throughout that area 
the largest numbers occur in and around the 
Fraser Valley, west to the Fraser River mouth 
(Campbell et al. 1974). Few food habit studies 
have been carried out on the Barn Owl here 
(Cowan 1942; Doerksen 1969; M. Wainwright, 
unpublished); only Cowan (1942) presented 
food habit data over a period of at least one year. 
Our paper presents data on the seasonal food 
habits of the Barn Owl on the Alaksen National 
Wildlife Area, in the Fraser River delta, British 
Columbia, for the period September 1974 to 
December 1975. 

Study Area 

The Alaksen National Wildlife Area is 
situated on Westham and Reifel Islands, deltaic 
islands in the Fraser River mouth, approxi- 
mately 32 km south of Vancouver, British 
Columbia. Both islands have been dyked and are 
now primarily agricultural areas. Most of the 
study area (270 ha) is cleared fields, either under 
cultivation or grassland. Hedgerows along dykes 
and waterways consist of mixed conifers and 
deciduous trees. It was estimated that from two 
to four Barn Owls frequented the area during the 
study period. Although three barns are on the 
Wildlife Area, interior access to them was 
limited and as a result they were not used 
extensively by the owls. A number of Wood 



Duck {Aix sponsa) nest boxes were located 
throughout the Wildlife Area, both the hori- 
zontal and vertical types similar to those 
described by Bellrose (1976), and both types 
were used as nest sites by Barn Owls. 

Adjoining the study area to the southwest is 
the George C. Reifel Migratory Bird Sanctuary 
which, along with Alaksen supports Canada's 
largest wintering population of waterfowl, as 
well as large numbers of resident and migrant 
shorebirds and songbirds. In total, over 230 
species of birds and 12 species of mammals have 
been sighted on these two islands (British 
Columbia Provincial Museum files). 

Methods 

Barn Owl pellets were collected from three 
main roosts: one in a fencerow of Red Cedar 
{Thuja plicata), one in a hedgerow of Pacific 
Crabapple (Pyrusfusca), and one in a small Red 
Alder {Alnus rubra) - crabapple woodlot. Each 
roost site was cleared of pellets in early 
September 1974 and collections were made at 
least monthly until December 1975. Pellets were 
gathered, placed in plastic bags, and subse- 
quently frozen until dissection took place. 
Whole pellets only were used for analysis. 

Two methods of pellet dissection were used. 
The first consisted of thawing and drying the 
pellets, taking their measurements, then teasing 
them apart to reveal the prey items. Those items 
were identified, numbered, recorded, and stored 



151 



152 



The Canadian Field-Naturalist 



Vol. 92 



in small paper envelopes. A second method 
involved the use of chemicals. Dry pellets were 
measured, then placed individually in 8-oz glass 
jars and covered with a 1-M solution of 
potassium hydroxide. After the contents of each 
jar had soaked for 12 h, they were poured into a 
fine mesh sieve and rinsed with fresh water to 
remove the dissolved hair. Prey items were then 
recorded as previously noted. The latter method 
proved to be the easier and more efficient. Loss 
of skull characteristics that might aid identifica- 
tion was not noted. 

Mammals remains were identified using Hall 
and Kelson (1959), Maser and Storm (1970), 
Banfield (1974), Cowan and Guiguet (1975), and 
by comparison with specimens from the British 
Columbia Provincial Museum and the Cowan 
Vertebrate Museum at the University of British 
Columbia. Shrews identifiable to species all 
appeared to be Vagrant Shrews, Sorex vagrans. 
As well, David Hawes (personal communica- 
tion) reports 5'orejc vagrans to be the only shrew 
species found on Westham Island. We have 
therefore reported all shrew remains to be that 
species. Identification of all bird remains was 
verified at the Provincial Museum. 

The number of individuals was determined as 
described in Cowan (1942). In calculating 
biomass, an average weight for each animal was 



determined from Cowan (1942), Banfield (1974), 
and Burt and Grossenheider (1976). As in other 
studies (Cowan 1942; Glue 1974), the majority of 
Rattus sp. prey in our study were juveniles as 
evidenced by the lack of wear of the cheek teeth 
and the size of the skull. Thus an average weight 
of 100 g was assumed for this genus (Glue 1974). 

Results 

From 497 pellets, 1156 individual prey 
animals were recovered, including six species of 
mammals, nine species of birds, three insects, 
two fish, and one crustacean (Table 1). 
Townsend's Vole, Microtus townsendii, formed 
79.9% of the total prey items recovered over the 
study period, followed by Sorex vagrans ( 10.6%) 
and Rattus sp. (4.8%). Passerine birds found in 
the pellets accounted for 2.2% of the prey 
composition. Other items recovered include fish 
gill plates, beetle elytra, duck trachea and 
vertebrae, and one sowbug. 

Frequency of occurrence of each prey species, 
that is the percentage of pellets in which a prey 
species occurs, is shown in Table 2. Mammalian- 
prey biomass is shown in Table 3. Because 
Muskrat (Ondatra zibethicus) does not appear 
to be a normal prey item in the diet of the Barn 
Owl, it has been omitted from the latter table. 

The mean number of prey animals per pellet 



Table I — Species composition of prey items in Barn Owl pellets collected on the Alaksen National Wildlife Area 



Species 


1974 






1975 






Com 


position 


Sept. 


-Dec. 


Jan.- 
Total 


Apr. 


May-Aug. 
Total % 


Sept.-Dec. 
Total % 






Total 


% 


Total 


% 


Sowbug 










1 


.4 






1 


.1 


Insect remains 










3 


I.l 






3 


.3 


Unidentified fish 














2 


.5 


2 


.2 


Unidentified duck 


3 


1.2 














3 


.3 


Passerines' 


5 


1.9 


5 


2.4 


7 


2.5 


9 


2.2 


26 


2.2 


Sorex vagrans 


17 


6.5 


23 


11.2 


42 


14.9 


41 


lO.O 


123 


10.6 


Peromvscus maniculatus 


1 


.4 


3 


1.5 






2 


.5 


6 


.5 


Microtus townsendii 


220 


84.3 


154 


75.1 


219 


77.9 


331 


80.9 


924 


79.9 


Ondatra zibethicus 










1 


.4 






1 


.1 


Rattus norvegicus 


10 


3.8 


15 


7.3 






22 


5.4 


47 


4.1 


Rattus sp. 


3 


1.2 






3 


1.1 


2 


.5 


8 


.7 


Zapus trinotatus 


2 


.7 


5 


2.4 


5 


1.7 






12 


1.0 


Total prey animals 


261 


100.0 


205 


99.9 


281 


100.0 


409 


100.0 


1156 


100.0 


Total pellets 


121 




73 




97 




206 




497 




Prey-animals per pellet 


2.16 




2.81 




2.90 




1.99 




2.33 





'Unidentified passerines 1 1, Troglodytes troglodytes 1, Sturnus vulgaris^. Aeglaius phoeniceus 1, Carpodacus purpureus 1, 
C. mexicanus 1 , Pipilo erythophthalmus 1 , Junco hyemalis 2, Melospiza melodia 1. 



1978 



Dawe et al.: Barn Owl Food Habits, British Columbia 



153 



Table 2 — Frequency of occurrence of prey in Barn Owl pellets from the Alaksen National Wildlife Area 



Frequency of occurrence (%) 


1974 




1975 




Average 


Sept. -Dec. 


Jan. -Apr. 


May-Aug. 


Sept. -Dec. 




Sowbug 






I.O 




.3 


Insect remains 






3.1 




.8 


Unidentified fish 








1.0 


.3 


Unidentified duck 


2.5 








.6 


Passerines 


4.1 


6.8 


5.1 


3.9 


5.0 


Sorex vagrans 


11.6 


27.0 


27.8 


16.0 


20.6 


Peromvscus maniculatus 


.8 


4.1 




1.0 


1.4 


Microtus townsendii 


91.7 


95.9 


93.8 


86.4 


92.0 


Ondatra zibethicus 






1.0 




.3 


Rattus sp. 


9.9 


17.6 


3.1 


9.7 


10.1 


Zapus trinolatus 


1.6 


6.8 


4.1 




3.1 



ranged from 1.99 to 2.90 through the study 
period with a total mean of 2.33. 

From a random selection of 100 pellets, sizes 
ranged in length from 30 mm to 84 mm and in 
width from 19 mm to 44 mm. The mean pellet 
size was 56 mm by 32 mm, which is slightly 
larger than measurements given by Burton 
(1973) and Webster (1973). 

Discussion and Conclusions 

Analysis of food habits of the Barn Owl in our 
study revealed prey species consistent with those 
of other studies (Cowan 1942; Doerksen 1969; 
M. Wainwright, unpublished) for southwestern 
British Columbia. Coast Moles, Scapanus 
orarius, contributed significantly to the diet of 
the Barn Owl in Cowan's (1942) study; however, 
to our knowledge this mammal does not occur 
on our study area. Microtus sp. appear to be one 
of the most important items in the Barn Owl's 



diet throughout much of North America (Foster 
1927; Boyd and Shriner 1954; Giger 1965; Maser 
and Brodie 1966; Maser 1972; Marti 1973) and 
Britain (Glue 1974). In our study M. townsendii 
occurred with an average frequency of 92.0% 
(Table 2), indicating further the importance of 
this small mammal to the diet of the Barn Owl. 
Microtus townsendii was the only species we 
recovered of that genus, notably one of the 
largest species in the genus. Other authors, 
however, have indicated, from pellet analysis, 
the presence of Long-tailed Voles, M. longicau- 
dus, on Westham Island (Campbell et al. 1972). 
Although the percent composition and fre- 
quency of occurrence can serve to indicate the 
relative importance of various prey species, 
biomass comparisons of the prey species indicate 
this importance far more accurately. GoUey 
(1961) has shown that the average energy values 
per unit mass of animals do not differ 



Table 3 — Estimated biomass' of Barn Owl mammalian-prey on the Alaksen National Wildlife Area. 



Species 


1974 






1975 






Total 




Sept. 


Dec. 


Jan. 
Bio- 


-Apr. 


May- 
Bio- 


-Aug. 


Sept.- 
Bio- 


-Dec. 








Bio- 




Bio- 






mass 




mass 




mass 




mass 




mass 






(g) 


% 


(g) 


% 


(g) 


% 


(g) 


% 


(g) 


% 


Sorex vagrans 


102 


1.0 


230 


2.8 


270 


2.7 


246 


1.5 


848 


1.9 


Perom vscus maniculatus 


18 


.2 


54 


.6 






36 


.2 


108 


.2 


Microtus townsendii 


9240 


86.4 


6468 


77.6 


9198 


93.4 


13902 


83.8 


38808 


85.4 


Rattus sp. 


1300 


12.1 


1500 


18.0 


300 


3.1 


2400 


14.5 


5500 


12.1 


Zapus trinotatus 


32 


.3 


80 


1.0 


80 


.8 






192 


.4 


Total mammalian biomass 


10692 


100.0 


8332 


100.0 


9848 


100.0 


16584 


100.0 


45456 


100.0 



'Average weights used in calculating mammalian-prey biomass were Sorex vagrans 6 g; Peromvscus maniculatus 18 
Microtus townsendii 42 g; Rattus sp. 100 g; Zapus trinotatus 16 g. 



154 



The Canadian Field-Naturalist 



Vol. 92 



significantly. Prey species biomass can therefore 
be compared. In our study (Table 3) Rattus sp. 
contributed far more significantly (12.1%) to the 
owl's diet than did Sorex vagrans (1.9%) even 
though Rattus sp. occurred in fewer numbers 
and in a lower frequency. Microtus townsendii, 
contributing 85.4% of the mammalian-prey 
biomass, formed the most significant portion of 
the owl's diet. 

Our study with an average of 2.33 prey 
animals per pellet is relatively consistent with 
studies carried out by Maser and Brodie (1966: 
Polk County, 2.2) and M. Wainwright (un- 
published: Delta, 2.18) while differing from 
those given by Doerksen (1969, 3.3), Giger 
(1965,4.0), and Maser and Brodie(1966: Benton 
County, 1.4). The differences appear to depend 
on the percent composition of relatively large- 
biomass prey animals in the diet, particularly 
Microtus sp. Where the percentage of Microtus 
sp. is high (e.g., Maser and Brodie 1966: Benton 
County, 90.96%) the number of skulls per pellet 
is lower than that when the percent composition 
is low (e.g., Giger 1965, 53.4%; Doerksen 1969, 
76.14%) and the diet does not include other 
large-biomass prey animals such as Rattus sp. 
This seems reasonable, for the owl would have 
to increase its intake of small-biomass animals in 
the latter case in order to maintain the same level 
of energy input. 

All of the prey species of the Barn Owl in this 
study have been captured or observed on the 
study area by the authors with the exception of 
Pacific Jumping Mice, Zapus trinotatus. As 
well, considerable data have been gathered by 
University of British Columbia researchers on 
Microtus townsendii populations for parts of 
our study area. Boonstra (1977) reports M. 
townsendii numbers on a 0.7-ha grid ranging 
from a peak of 23 1 animals in 1 972 to a low of 46 
animals in the spring of 1973. He indicated the 
population seemed to be going through a typical 
cycle. Boonstra (1977) also mentions that Sorex 
vagrans was common but at very low densities 
(two to six per hectare). 

The common prey species of the Barn Owl at 
Alaksen are those that frequent the owl's favored 
hunting habitat and, like the owl, are primarily 
nocturnal. Only one mammal species that 
frequented treed habitats (Deer Mice, Pero- 
myscus nianiculatus) was found in the pellets, as 



was the case in Cowan's (1942) study. It 
appeared during the cool wet months of the year, 
possibly when the availability of favored prey 
decreased. The frequency of occurrence of M. 
townsendii remained relatively stable, dropping 
only slightly in the two September-December 
periods. Sorex vagrans occurred in the owl's diet 
with greater frequency during the summer 
months presumably owing to the addition of 
young animals to the population along with their 
increased movements and higher vulnerability. 
The frequency of Rattus sp. on the other hand, 
decreased dramatically during the summer. This 
may have been a result of the greater availability 
of favored or easier-to-catch prey species during 
that period, as postulated with S. vagrans. Other 
authors (Cowan 1942; Glue 1974) have men- 
tioned the apparent reluctance of the Barn Owl 
to capture large prey such as Rattus sp. The 
presence of a juvenile Muskrat is thus likely an 
incidental occurrence in the Barn Owl's diet. We 
could find no evidence in the literature of 
Muskrats being recorded as anything but an 
incidental prey item of the Barn Owl (Marti 
1973; M. Wainwright, unpublished). Juvenile 
Muskrats may be near the limit in size and 
aggressiveness that Barn Owls will attempt to 
capture, although some surprisingly large and 
aggressive animals (e.g., cottontails, Sylvilagus 
sp., and weasels, Mustela sp.) have been 
reported in the diet of Barn Owls (Otteni et al. 
1972; Banks 1965; M. Wainwright, unpub- 
lished). There is, of course, the possibility that 
the owl was scavenging an already dead 
Muskrat. 

All species of birds whose remains occur in the 
pellets (Table 1) are common at Alaksen and all 
but the Starling (Sturnus vulgaris) commonly 
frequent the woodlot edges and hedgerows. 
Most birds that fell prey to the owls were 
probably taken from their evening roosts. Since 
Starlings and Barn Owls are both known to use 
Wood Duck nest boxes it is not inconceivable 
that Starlings were occasionally trapped and 
captured in such a nest box. The frequency of 
occurrence of passerine birds in the Barn Owl's 
diet remained relatively stable throughout the 
year with only a slight increase in the spring and 
summer months. 

Insect remains have been reported in other 
studies (Cowan 1942; Earhart and Johnson 



1978 



Dawe et al.: Barn Owl Food Habits. British Columbia 



155 



1970; Glue 1974), and Burton (1973) notes that 
Barn Owls have been seen "plunging into a pool 
like an osprey to seize a fish." Those items 
formed a negligible part of the Barn Owl's diet in 
our study, however, and must be considered 
incidental to the owl's diet. 

Acknowledgments 

We thank Rudy Boonstra, University of 
British Columbia, for his assistance during the 
initial stages of our study. For their helpful 
suggestions and criticisms we are sincerely 
grateful to R. Wayne Campbell, British Colum- 
bia Provincial Museum, and R. D. Harris and 
John P. Kelsall, Canadian Wildlife Service, 
Pacific and Yukon Region. We also express our 
appreciation to the referees for their comments 
on the manuscript. 

Literature Cited 

Banfield, A. W. F. 1974. The mammals of Canada. Uni- 
versity of Toronto Press, Toronto. 
Banks, R. C. 1965. Some information from Barn Owl 

pellets. Auk 82: 506. 
Bellrose, F. C. 1976. Ducks, geese, and swans of North 

America. Stackpole Books, Harrisburg, Pennsylvania. 
Boonstra, R. 1977. Predation on Microlus townsendii 

populations: impact and vulnerability. Canadian Journal 

of Zoology 55: 1631-1643. 
Boyd, E. M. and J. Shriner. 1954. Nesting and food of the 

Barn Owl (Tvto alba) in Hampshire County. Mass. Auk 

71: 199-210. 
Burt, W. H. and R. P. Grossenheider. 1976. A field guide 

to the mammals. Houghton Mifflin Co., Boston. 
Burton, J. A. (Editor). 1973. Owls of the world. E. P. 

Dutton and Co. Inc., New York. 
Campbell, R. W., M. G. Shepard, and W. C. Weber. 1972. 

Vancouver birds in 1971. Vancouver Natural History 

Society, Special Publication Number 2. 



Campbell, R. W., M. G. Shepard, B. A. Macdonald, and 

W.C.Weber. 1974. Vancouver birds in 1972. Vancouver 

Natural History Society, Special Publication Number 4. 
Cowan, I. McT. 1942. Food habits of the Barn Owl in 

British Columbia. Murrelet 23: 49-53. 
Cowan, I. McT. and C. J. Guiguet. 1975. The mammals of 

British Columbia. British Columbia Provincial Museum 

Handbook Number 11. 
Doerksen, G. F. 1969. An analysis of Barn Owl pellets 

from Pitt Meadows, British Columbia. Murrelet 50: 4-8. 
Earhart, C. M. and N. K. Johnson. 1970. Size dimorphism 

and food habits of North American owls. Condor 72: 

251-264. 
Foster, G. L. 1927. A note on the dietary habits of the 

Barn Owl. Condor 29: 246. 
Giger, R. D. 1965. Surface activity of moles as indicated 

by remains in Barn Owl pellets. Murrelet 46: 33-36. 
Glue, D. E. 1974. Food of the Barn Owl in Britain and 

Ireland. Bird Study 21: 200-210. 
Godfrey, W. E. 1966. The birds of Canada. National 

Museum of Canada Bulletin Number 203. 
Golley, F. 1961. Energy values of ecological materials. 

Ecology 42: 581-583. 
Hall, E. R. and K. R. Kelson. 1959. The mammals of North 

America. 2 volumes. Ronald Press, New York. 
Marti, C. D. 1973. Ten years of Barn Owl prey data from a 

Colorado nest site. Wilson Bulletin 85: 85-86. 
Maser, C. 1972. A note on the food habits of Barn Owls 

in Klamath County, Oregon. Murrelet 53: 28. 
Maser, C. and E. D. Brodie, Jr. 1966. A study of owl pellet 

contents from Linn, Benton, and Polk Counties, Oregon. 

Murrelet 47: 9-14. 
Maser, C. and R. M. Storm. 1970. A key to Microtinae of 

the Pacific Northwest. Oregon State University Book 

Stores Inc., Corvallis, Oregon. 
Otteni, L. C, E. G. Bolen, and C. Cottam. 1972. Predator- 
prey relationships and reproduction of Barn Owls in south 

Texas. Wilson Bulletin 84: 434-438. 
Webster, J. A. 1973. Seasonal variations in mammal con- 
tents of Barn Owl castings. Bird Study 20: 185-186. 

Received 29 September 1977 
Accepted 8 February 1978 



Demographic and Dietary Responses of Great 
Horned Owls during a Snowshoe Hare Cycle 

Robert S. Adamcik, Arlen W. Todd,' and Lloyd B. Keith 



Department of Wildlife Ecology, University of Wisconsin, Madison 53706 

I Present Address: Department of Recreation, Parks and Wildlife, Edmonton, Alberta 

Adamcik, R. S., A. W. Todd, and L. B. Keith. 1978. Demographic and dietary responses of Great Horned Owls during a 
a Snowshoe Hare cycle. Canadian Field-Naturalist 92(2): 156-166. 

Population demography and food habits of Great Horned Owls {Bubo virginianus) on 162 km- in central Alberta during 
1966-1975 were importantly affected by a cyclic fluctuation of Snowshoe Hares (Lepus americanus). Non-breeding was 
observed among territorial pairs of owls when estimated hare densities on 1 April were below 0.9/ ha of habitat. Mean clutch 
size among owls exhibited significant yearly variation which could be only in part related to Snowshoe Hare and small- 
mammal densities. Snowshoe Hares were totally absent from the spring diet of horned owls by 1975 when hares were scarce, 
but still comprised 50% of the owls' food consumption in winter. Functional (dietary) responses to changing Snowshoe Hare 
densities produced changes in the biomass of food supplied to young owls that paralleled the hare cycle. The amplitude of 
fluctuation in horned owl numbers at Rochester was markedly increased by ingress during 1967-1971 and egress during 
1972-1975. Territoriality may have prevented a further increase in the peak owl population between 1971 and 1972. Theowls 
declined 1 year after the hares, but would have declined 2 years after if a major emigration had not occurred in 1972-1973. 
Mean rates of nesting by yearling horned owls have been estimated at 21 and 24%. 

Key Words: predation, cycles, raptors, hares, boreal forest. 



A study of Great Horned Owls {Bubo 
virginianus) was conducted in central Alberta 
during 1966-1975. Its objective was to examine 
changes in the demography and food ecology of 
the owl population over one complete cycle of 
abundance of the Snowshoe Hare {Lepus 
americanus). Early results of this work were 
reported by Rusch et al. (1972) and Mclnvaille 
and Keith (1974). These investigators evaluated 
findings through 1971, the year of peak spring 
densities of hares on the study area. They 
examined intraspecific relationships among the 
owls and interspecific relationships with the 
Red-tailed Hawk {Buteo jamaicensis) popula- 
tion. They also examined the effect of increasing 
hare densities on the breeding biology of the 
horned owls and certain interactions with prey 
species other than the hare. 

Snowshoe Hares declined at Rochester after 
spring 1971, reaching the lowest point in their 
cycle by spring 1975. This paper describes the 
dynamics of the horned owl population, its 
dietary response to declining hare densities, and 
probable applications of our Rochester findings 
to northern horned owl populations generally. 

Study Area and Methods 

The 1 62-km- study area ( 1 30 km- in 1 966) was 
a block of mixed agricultural and forested land 



near Rochester, Alberta, 97 km north of 
Edmonton. Luttich et al. (1971) and Rusch etal. 
(1972) described the vegetation, topography, 
and land-use practices on the area. Mclnvaille 
and Keith (1974) classified the major habitats 
and outlined their distribution as of 1971. 
Except for continued revegetation of burned 
areas, and minor clearing of forested land for 
pasture, the area remained unchanged over the 
next 4 years. 

Methods of censusing raptors, tethering 
nestlings for food studies, and estimating prey 
population densities were identical to those 
described by Mclnvaille and Keith (1974). 
Estimates of Snowshoe Hare and Ruffed Grouse 
{Bonasa umbellus) numbers have been revised 
slightly, however, as additional analyses were 
completed. We expanded small-mammal moni- 
toring to include a spring (April-May) index 
during 1973-1975. Waterfowl population in- 
dices were based on aerial counts along a 0.4- 
km-wide transect between the towns of Cold 
Lake and Swan Hills, passing 11 km north of 
Rochester. 

Results and Conclusions 

Prey Populations 

Spring ( 1 April) densities of Snowshoe Hares 
near Rochester peaked in 1971 at 510/ 100 ha of 



156 



1978 



Adamcik et al.: Great Horned Owls and Snowshoe Hares 



157 



Table 1 — Estimated densities and population indices of prey on the raptor study area near Rochester, Alberta 



Species density 
























or index 


Months 


1966 


1967 


1968 


1969 


1970 


1971 


1972 


1973 


1974 


1975 


Snowshoe Hares/ 
























100 ha' 


1 Apr. 


24 


39 


93 


144 


340 


510 


245 


78 


23 


5 


Ruffed Grouse/ 100 ha2 


Apr.-May 


32 


35 


61 


42 


46 


32 


16 


15 


15 


34 


Sharp-tailed Grouse 
























dancing ground^ 


Apr.-May 


10 


14 


25 


31 


49 


10 


4 


22 


19 


20 


aerial count* 


Nov. -Mar. 


54 


62 


54 


70 


112 


8 


39 


15 


8 


4 


Voles and mice/ 
























1000 trap-nights* 


Aug.-Sept. 
Apr.-May 


57 


160 


92 


136 


82 


67 


142 


95 
20 


101 

38 


38 
30 


Waterfowl' 


May 












120 


101 


94 


95 


63 



'Mean number of adults on four study areas. Density estimates for 1966-1971 have been revised since the publication of 

Mclnvaille and Keith (1974), but population trend was similar. 
2Mean number of adults on four study areas. Density estimates for 1966-1971 have been revised since the publication of 

Mclnvaille and Keith (1974), but population trend was similar. 
^Maximum number of males observed on one dancing ground near Rochester. 
'•Original dancing ground was abandoned; the new one was located in 1973. 
'Mean number observed per 100 km- during two to five helicopter flights covering approximately 180 km^ and overlapping 

about half the raptor study area. 

^Microtus pennsylvanicus, Peromyscus maniculatus, Clethrionomys gapperi. 
^Number of individuals observed in a 0.4-km aerial transect between the towns of Cold Lake and Swan Hills. The transect 

passed about 11 km north of Rochester. (Data courtesy of K. Duane Norman, U.S. Fish and Wildlife Service.) 



habitat, then declined more than 50% by 1972. 
By 1975 there were 5 hares/ 100 ha, only 1% of 
peak levels (Table 1). 

Ruffed Grouse densities were highest in spring 
1968 at 61 / 100 ha of habitat. A 65% decline to 
16/ 100 ha occurred between the springs of 1970 
and 1972. Densities remained low through 
spring 1974, then more than doubled by 1975. 
There was a marked decrease among Sharp- 
tailed Grouse (Pedioecetes phasianellus) be- 
tween 1970 and 1971. Numbers thereafter 
remained relatively low through 1975. Water- 
fowl indices for 1971-1975 indicated an overall 
decline of about 50%. 

During 1971-1975, small-mammal popula- 
tions continued to fluctuate markedly. There 
had been fall population peaks in 1967 and 1969, 
and another occurred in 1972; there were lows in 
1971 and 1975. Spring populations were higher 
in 1974 than in 1973 and 1975 (Table 1). 

Great Horned Owl Numbers and Reproduction 
Great Horned Owls increased on the study 
area from 5 pairs (1 breeding) in 1966 to at least 
16 pairs (all breeding) by 1971. There were also 
16 breeding pairs in 1972; but the population 
decreased thereafter to 5 pairs by 1975. Nesting 



attempts ceased during this decline, with only 1 
of 13 pairs laying eggs in 1973 and none of 8 and 
5 pairs in 1974 and 1975 (Table 2). Although we 
could not be certain of the total number of 
resident pairs present during 1970 1972, we 
believe that no non-breeding territorial pairs 
were missed; and thus, as in 1968 and 1969, total 
breeding pairs equalled total resident territorial 
pairs. 

The mean date of hatching for horned owl 
clutches was slightly later in 1972 (21 April) than 
in 1970 and 1971 (14 and 18 April, respectively),. 
though still earlier than in 1967-1969 (range 28 
April - 4 May). Mean clutch size varied signifi- 
cantly (P<0.05) among years, being largest 
(3.1) in 1970 and smallest (1.9) in 1969. Hatching 
success averaged 98% (range 94-100%) for all 
years except 1971. In 1971, hatching success 
dropped to 84%. Of the five pairs not hatching 
complete clutches that year, three were late 
nesters. Mclnvaille and Keith (1974) believed 
that these were yearlings, breeding a year ahead 
of the normal because of peak hare densities. 

The nature of spacing within the 1972 horned 
owl population was tested for randomness using 
Clark and Evans' (1954) "nearest neighbor test" 
(see Mclnvaille and Keith 1974). As in earlier 



158 



The Canadian Field-Naturalist 



Vol. 92 



Table 2 — Some population statistics for the Great Horned Owl on a 162-km- area (130 km- in 1966) near Rochester, 
Alberta 









1966 


1967 


1968 


1969 


1970 


1971 


1972 


1973 


1974 


1975 


Resident territorial pairs 






5 


6 


8 


9 


■71 


7 


7 


13 


8 


5 


Breeding (laying) 






1 


3 


8 


9 


7 


16 


16 


1 








Non-breeding (non-laying) 






4 


3 








7 


7 


7 


12 


8 


5 


Eggs hatched/ successful nest^ 






2.0 


2.3 


2.1 


1.9 


3.1 


2.0 


2.6 


3 


— 


— 


Percent mortality of young from 


hatch 


ng 






















to fledging'* 









11 


25 


19 


14 


9 


29 





— 


— 



'Increased number of owls and apparent movements from winter hooting positions to spring nesting sites prevented 

accurate estimates of total resident pairs. 
^These figures include some nests not on the 162-km- area: i.e., one in 1966, five in 1967, three in 1968, one in 1969, two in 1970, 

six in 1971, and four in 1972. 

-^The single active nest in 1973 failed prior to hatching. 
■•Young dying from handling and starvation were treated as unnatural mortality and excluded from this sample because such 

losses did not appear among untethered birds off the study area. 



years, the distribution of owl pairs on the study 
area was significantly (jP<0.05) regular, thus 
indicating the continued influence of ter- 
ritoriality as a spacing mechanism within the 
breeding population. 

Relationship between Breeding Activity 
and Snowshoe Hare Density 

Our data suggest that there may be a critical 
overwinter hare density below which breeding 
by the territorial owl population becomes 
depressed. When early spring hare densities were 
below 0.9/ ha of habitat, some resident pairs of 
horned owls failed to nest. In 2 of 5 such years, 
there were no known nesting attempts (Figure 1.) 

During a period of hare scarcity in the 1960s in 
Saskatchewan, Houston (1971) observed num- 
erous territorial pairs of horned owls for which 
he could find no nests. During the next hare 
decline, owl numbers on a 32-km- area dropped 
from at least nine pairs (all breeding) in 1971 to 
three (none breeding) in 1973 (Houston 1975). 
These data, in conjunction with ours at 
Rochester, indicate that changes in numbers and 
breeding rates of horned owls in response to 
varying hare densities are regional phenomena. 

Relationships between Clutch Size and 
Prey Density 

Large clutches in Tawny Owls {Strix aluco) 
have been associated with high prey populations 
(Southern 1959); and Houston (1971) reported 
the largest clutches of horned owls in Saskatche- 
wan in years of peak hare and/ or mouse 
densities. Increases in clutch size in high prey 
years have been observed in several other species 



of owls as well (Lack 1966, pp. 146-147). 

A similar relationship existed with horned 
owls at Rochester. For example, in spring 1970, 
when Microtus pennsylvanicus were conspicu- 
ously abundant and hares were near their peak, 
mean clutch size was the largest recorded (3.1). 
In 1967, small mammals were abundant and 
hares were scarce, whereas in 1971 the situation 
was reversed: in these two years average clutch 
size was intermediate (2.4). In 1968 and 1969, 
small mammals were apparently not abundant, 
as evidenced by spring food habits (discussed 
later), and hare densities were intermediate: in 
these two years average clutch size was smallest 
(2.0). 

The situation in 1972 was, however, ano- 
malous: small mammals were little utilized and 
hence probably scarce, and hares were reduced 
to intermediate levels; yet mean clutch size (2.7) 
was the second largest recorded. 

Ingress and Egress 

We calculated net ingress or egress annually 
(Table 3) from observed changes in numbers of 
territorial pairs and fledged young at Rochester, 
together with post-fledging mortality rates 
obtained through life-table analyses of regional 
banding data (Adamcik and Keith 1978). The 
term 'net' is emphasized because young horned 
owls apparently disperse from natal territories 
after fledging. Such movements are usually 
short-range (within 80 km) and directionally 
unpredictable (Stewart 1969; Adamcik and 
Keith 1978), but would likely carry young 
fledged on our study area beyond its boundaries. 



1978 



Adamcik et al.: Great Horned Owls and Snowshoe Hares 



159 



5 

O 20 




1970 1971 1972 1973 1974 1975 



Figure 1 . Relationship between Great Horned Owl nesting and estimated densities of Snowshoe Hares on a 1 62-km- study 
area (130 km- in 1966), 1 April, near Rochester, Alberta. Figures in parentheses are known numbers of territorial 
pairs of owls on the area. 



while young fledged elsewhere may or may not 
move into the area. If the number leaving 
equalled the number arriving, net ingress and 
egress would both be zero. 

Mean annual mortality rates of Great Horned 
Owls banded as nestlings in forest and parkland 
regions of Alberta, Saskatchewan, and Mani- 
toba were 55% in the first year of life, 39% in the 
second, and 22% thereafter (Adamcik and Keith 
1978). There was no detectable difference in 
post-fledging mortality as owl populations 
increased and decreased in relation to the hare's 
cyclic fluctuations; hence, we applied the same 
mean rates of mortality each year when 
calculating ingress and egress at Rochester 
(Table 3). 

Ingress contributed importantly to the in- 
crease of horned owls at Rochester during 
1966-1971 (Table 3). If, as is generally beheved, 



territoriality and nesting are not evident among 
yearlings (birds approaching 1 year of age), then 
ingress accounted for between 31 and 58% of the 
territorial owls present during 3 years of 
population growth. If all yearlings had entered 
the territorial cohort, ingress would still have 
exceeded 30% in 3 of 5 years from 1967 to 1971. 
Conversely, egress played a major role in the 
ensuing population decline, being equivalent to 
62% of the remaining territory holders in 1974 (if 
these were adults only), and 35% in 1973 (if both 
yearlings and adults were territorial). Overall, 
increases in numbers were always associated 
with ingress and decreases were associated with 
egress. 

Food Habits 

Snowshoe Hare biomass in the spring diet of 
horned owls exhibited an approximately four- 



160 



The Canadian Field-Naturalist 



Vol. 92 



Table 3— Calculated ingress and egress of Great Horned Owls on a 162-km- study area near Rochester, Alberta. Post- 
fledging survival rates based on analysis of horned owl banding data from forest and parkland regions of Alberta, 
Saskatchewan, and Manitoba 









Numbers of Great h 


orned Owls in 


different age 


classes 






1966 


1967 


1968 


1969 


1970 


1971 


1972 


1973 


1974 


1975 


Observed: Territorial owls (A) 


10 


12 


16 


18 


14 


32 


32 


26 


16 


10 


Expected survivors 


Aduhsi (B) 




6.8 


8.2 


10.9 


12.2 


9.5 


21.8 


21.8 


17.7 


10.9 


from previous year: 
























Observed: 


Fledglings 


2 


6 


13 


14 


19 


29 


30 











Expected survivors 


Yearlings^ (C) 




0.9 


2.7 


5.9 


6.3 


8.6 


13.1 


13.5 








from previous year: 


Adults^ (D) 






0.5 


1.6 


3.6 


3.8 


5.2 


8.0 


8.2 





Net ingress: 
























If both adults and yearlings 






4.3 


5.1 


1.2 




13.9 










territorial = A-(B+C) 






(36%) (32%) 


(7%) 




(43%) 










If adults only territorial = 








7.3 


5.5 




18.7 


5.0 








A-(B+D) 








(46%) (31%) 




(58%) (16%) 








Net egress: 
























If both adults and yearlings 












4.5 




2.9 


9.3 


1.7 


0.9 


territorial = A-(B+C) 












(32%) 




(9%) 


(35%) (11%) 


(9%) 


If adults only territorial = 












1.8 






3.8 


9.9 


0.9 


A-(B+D) 












(13%) 






(15%) (62%) 


(9%) 



'Based on a mean annual survival rate 0.68; this is the average survival for horned owls after 1 year of age. This value was used 
since it was not known if the "territorial owls" consisted of yearlings as well as adults. 
^Based on a mean annual survival rate during the first year after fledging of 0.45. 
^Based on a mean annual survival rate during the second year after fledging of 0.61. 



fold increase (from 23 to 81%) during the 
1966-1971 upswing in the hare cycle. Con- 
comitant with the subsequent decline in hare 
numbers was decreased utilization to zero by the 
1975 nesting season. Birds in general, and 
waterfowl in particular, exhibited the opposite 
trend in the owls' diet, and were evidently 
strongly buffered when hares were abundant 
(Table 4). The relative importance of small 
mammals in the diet was lowest in 1968, 1969, 
1971, and 1972, and thus not predictably related 
to their own abundance or that of the hare 
(Table 1). There were, however, notable in- 
creases in consumption of voles, weasels, and 
Red Squirrels [Tamiasciurus hudsonicus) dur- 
ing 1974 and 1975 as hares declined to extreme 
scarcity. 

The winter diet of horned owls during 
1971-1972 to 1974-1975 was apparently much 
more stable, despite the steady decline in hare 
densities. Total food biomass was at least 90% 
Snowshoe Hare through 1973-1974. In 1974- 
1975, hares were at their lowest level, but still 
the forest zone when hares had become scarce. 
We think it much less likely that the apparent 



staple food item reflects the simplicity of the prey 
base at Rochester in winter; there are few 
alternative prey species. 

Dietary Biomass of Prey 

The dietary biomass of prey brought to 
tethered young owls (Table 6) increased sig- 
nificantly during the last 2 years of the hare 
population increase. Broods received an average 
of 347 g daily during 1967-1969, and 905 g daily 
during 1970 and 1971; individual young received 
175 and 370 g during the same periods. This 
marked rise was attributable to increased 
utilization of Snowshoe Hare during the last two 
years. The average biomass of hare supplied 
daily to individual young increased nearly four- 
fold (mean 78 g in 1967-1969 vs. 293 g in 
1970-1971), whereas that of other species 
changed little as hare densities rose. 

In 1972, the first spring of reduced hare 
numbers and the only one in which owls reared 
young, the average biomass supplied daily per 
brood and per individual young remained high 
(839 and 380 g, respectively). Hares comprised 
64% of the total dietary biomass in 1972 (Table 



1978 



Adamcik et al.: Great Horned Owls and Snowshoe Hares 



16! 



Table 4 — Spring (1 April - 30 June) food habits of Great Horned Owls near Rochester, Alberta' 











Percent 


freqi 


[lency 














Percent biomass 








Prey species- 


66 


67 


68 


69 


70 


71 


72 


73 


74 


75 


66 


67 


68 


69 


70 


71 


72 


73 


74 


75 


Snowshoe Hare 


2 


4 


10 


8 


13 


27 


23 


9 


2 





23 


34 


50 


50 


77 


81 


64 


70 


16 





Pocket Gopher 


12 


7 


19 


21 


2 


9 


7 


3 


6 


3 


15 


6 


10 


14 


1 


3 


2 


3 


8 


5 


Mice and voles 


73 


69 


54 


55 


80 


48 


37 


75 


78 


79 


18 


11 


6 


8 


12 


4 


2 


12 


22 


27 


Other mammals 


4 


3 


3 


1 


1 


2 


4 


2 


4 


4 


12 


7 


6 


1 


1 


1 


2 


1 


7 


39 


Total mammals 


91 


83 


86 


85 


96 


86 


71 


89 


90 


86 


68 


58 


72 


73 


91 


89 


70 


86 


53 


71 


Ruffed Grouse 


4 


2 


2 





tr' 


tr 


2 


1 








23 


6 


4 





1 


tr 


1 


1 








Sharp-tailed Grouse 





tr 


3 


1 


tr 


tr 


tr 














2 


10 


3 


tr 


tr 


tr 











Waterfowl 


1 


4 


4 


6 


2 


7 


23 


2 


4 


2 


7 


20 


10 


18 


7 


9 


26 


8 


24 


14 


Other birds 


4 


10 


5 


8 


3 


5 


4 


9 


7 


12 


2 


14 


3 


6 


1 


2 


2 


6 


24 


16 


Total birds 


9 


16 


14 


15 


5 


13 


29 


12 


11 


14 


32 


42 


27 


27 


9 


11 


29 


15 


48 


30 


Totals 


100 


99 


100 


100 


101 


99 


100 


101 


101 


100 


100 


100 


99 


100 


100 


100 


99 


101 


101 


101 



iTotal numbers of food items were 114, 986, 518, 338, 756, 775, 773, 204, 125, and 131 in 1966-1975; biomass totals (in 
grams) were 12 103, 174 786, 140 027,71 778. 193 736, 321489, 370 230, 36 335, 12 951, and 10 816, respectively. Sources 
of food habits data were pellets collected at adult roosts; and pellets and prey items collected at nest sites and sites at which 
young were tethered. 

-Prey not specifically identified in the table were as follows: "Mice and voles" — Microtus pennsylvanicus (averaged 
74% of small mammal biomass), Peromyscus maniculatus (20%), Clethrionomys gapperi{5%), Zapus hudsonius (trace), and 
Sorex cinereus (trace). "Other mammals" — Ondatra zibethicus, Tamiasciurus hudsonicus, Spermophilus richardsonii, 
S. franklinii, Glaucomys sabrinus. Mustela frenata, M. hxosa, M. erminea. "Waterfowl" — Anas platyrhynchos, A. acuta, 
A. strepera, A. discors, A. carolinensis, Mareca americana, Spatula clypeata, Aythya americana, A. collaris, A. affinis, 
Fulica americana, Bucephala albeola, Podiceps grisegena, Porzana Carolina, Rallus limicola. "Other Birds" — Falco 
sparverius, Accipter cooperii, Buteo jamaicensis, Columba livia, Perdix perdix. Phasianus colchicus. Pica pica, Perisoreus 
canadensis, Charadrius vociferus, Turdus migratorius, Dendrocopos villosus, Sphyrapicus varius, Sturnus vulgaris, 
Colaptes auratus, Dendroica petechia, and unidentified songbirds and domestic chickens. 

3Less than 0.5%. 



Table 5 — Winter (1 December - 31 March) food habits of Great Horned Owls near Rochester, Alberta' 







Percent 


frequency 










Percent biomass 




Prey species- 


1971-72 


1972- 


73 


1973-74 


1974- 


-75 


1971- 


72 


1972-73 


1973-74 


1974-75 


Snowshoe Hare 
Mice and voles 
Other mammals 
Total mammals 


89 



11 

100 


83 
9 
2 

94 




26 

67 

4 

97 


7 
78 

8 
93 




98 



2 

100 




97 
tr3 
tr 
98 


90 

5 

2 

97 


50 
13 
12 

75 


Ruffed Grouse 
Other birds 
Total birds 







5 

5 





4 
4 



8 
8 




• 






2 


2 




3 
3 



26 
26 


Totals 


100 


99 




101 


101 




100 




100 


100 


101 



'Food habits in winter were determined entirely from pellets collected at roosts. Total pellets were 9, 36, 1 Land 27 in 1971-72 
through 1974-75. Total number of food items were 9, 42, 27, and 77 in 1971-72 through 1974-75; biomass totals (in grams) 
were 1 1 000, 48 737, 10 508, and 13 649, respectively. 

-Prey not specifically identified in the table were as follows: "Mice and voles" — Microtus pennsylvanicus (averaged 54% 
of small mammal biomass), Peromyscus maniculatus (34%), Clethrionomys gapperi (9%), and Sorex cinereus (\%). "Other 
mammals" — Tamiasciurus hudsonicus, Mustela vision, M. erminea, M. frenata. and unidentified mammals. "Other 
birds" — Columba livia. Pica pica, Perdix perdix, and domestic chickens. 

^Less than 0.5%. 



162 



The Canadian Field-Naturalist 



Vol. 92 



Table 6 — Prey biomass (in grams) brought to tethered Great Horned Owl young 





1967 


1968 


1969 




1970 


1971 


1972 


Average biomass per day per brood' 
















Snowshoe Hare 


126 


175 


161 




734 


693 


537 


Other species 


245 


174 


160 




219 


163 


302 


Total 


371 


349 


321 




953 


856 


839 


Average biomass per day per young 
















Snowshoe Hare 


56 


85 


95 




253 


333 


243 


Other species 


110 


84 


95 




75 


78 


137 


Total 


166 


169 


190 




328 


411 


380 


'Numbers of Great Horned Owl broods 


tethered 


were 8. 8. 7, 8, 


9, and 


12 fr 


om 1967 to 


1972. respe 


ctively. 



4), indicating that their availability was still 
important in enabling adult horned owls to feed 
their young. 

Discussion 

A Life Equation for Northern Horned 
Owl Populations 

We found that when hares were scarce, 
reproductive recruitment to the owl population 
was low or zero with resident pairs failing to 
nest. This prompted construction of a life 
equation to assess the requisites for long-term 
maintenance of northern horned owl popula- 
tions. 

We assumed that mean clutch size, hatching 
success, and nestling survival rates at Rochester 
during 1966-1975 were representative of re- 
gional owl populations elsewhere in forested 
sections of the three Prairie Provinces. This 
assumption is consistent with previously pub- 
lished information (Henny 1972; Houston 1971; 
Murray 1976). We likewise assumed that 
estimates of post-fledging survival obtained 
from bandings since 1955 within this same 
ecosystem were applicable (Adamcik and Keith 
1978). 

Our life equation (Table 7) first examined the 
consequences of adults only breeding at the 
mean rate of 0.66 recorded among territorial 
pairs at Rochester during 1966-1975. The 
resulting life equation predicted a decreasing 
population, with 1000 eggs subsequently gener- 
ating 884 eggs. 

This projected decline of about 12% per 
generation (5.5 years) is inconsistent with the 
apparent long-term stability of horned owl 
populations in Canada and the United States 
(Fyfe 1976; Henny 1972). The least reliable 



components of our life equation are probably 
the post-fledging survival estimates which are 
based on only 155 band recoveries. The sensi- 
tivity of the life equation to minor errors in 
survival estimates is illustrated by the fact that 
an increase in first-year survival from only 0.45 
to 0.51 would produce population stability. 

An alternative explanation for the predicted 
population decline is that our assumption of 
non-breeding by yearlings is incorrect. The 
widely accepted idea that Great Horned Owls do 
not breed as yearlings seems to be wholly 
untested in the field, even though Hickey (1952) 
pointed out the need for such information 26 
years ago. In the most relevant paper, Weller 
(1965) concluded from bursa regression that: 
". . . most individuals do not breed until two 
years old, although some yearling females may 
breed." By 1 year of age the bursa was one-half to 
one-third its initial depth, and by 2 years was 
largely regressed. Weller also stated, however, 
that two females, in evident breeding condition, 
had bursas designating them as yearlings. That 
large owls have at least the potential to nest as 
yearlings was shown by Flieg and Meppiel's 
(1972) captive Snowy Owls {Nyctea scandiaca). 

Henny (1972) calculated a yearling nesting 
rate from the proportion of yearlings in the 
population (34%) as given by a life table, an 
overall non-nesting rate (26%) reported by four 
studies in the United States, and the assumption 
that all non-nesters were yearlings. Because of a 
minor computing error, Henny's estimate of 
23% yearling nesting should be revised slightly to 
2 1 %. This figure is very close to the 24% yearling 
nesting calculated by us (Table 7) as another way 
of balancing a life equation for northern Great 
Horned Owls. 



1978 



ADAMCIK ET AL.: GREAT HORNED OWLS AND SNOWSHOE HARES 



163 



Table 7 — Life equation for a Great Horned Owl population based on observed clutch size, hatching success, and nestling 
survival at Rochester, and subsequent survival rates calculated from banding data from forest and parkland regions of 
Alberta, Saskatchewan, and Manitoba 



Approximate 
age interval 



Age 
class 



Number 
alive at 
start of 
interval 



Interval 

survival 

rate' 



Proportion 
breeding- 



Eggs laid 



interval-' 



0-5 weeks 
5-10 weeks 

0.2-1.2 years 

1-2 years 

2-3 years 

3-4 years 

4-5 years 

5-6 years 

6-7 years 

7-8 years 

8-9 years 

9-10 years 
10-1 1 years 
11-12 years 
12-13 years 
13-14 years 
14-15 years 
15-16 years 
16-17 years 
17-18 years 
18-19 years 
19-20 years 
20-21 years 
21-22 years 
22-23 years 
23-24 years 
24-25 years 
25-26 years 
26-27 years 

Total eggs produced 



eggs 
nestlings 
nestlings 

and 
juveniles 
yearlings 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 
adults 



1000 
960 

883 

397 

242 

189 

147 

115 

90 

70 

55 

43 

33 

26 

20 

16 

12 

10 

7 

6 

5 

4 

3 

2 

2 

1 

1 

1 

1 



without breeding by yearlings 



0.96 
0.92 

0.45 

0.61 

0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 
0.78 



(0.24)" 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 
0.66 



(116) 

194 

152 

118 

92 

72 

56 

44 

34 

26 

21 

16 

13 

10 

8 

6 

5 

4 

3 

2 

2 

2 

I 

1 

1 

1 

884 



' We assumed that nestlings were banded on the average halfway between hatching and fledging. Since nestling survival from 
hatching to fledging averaged 0.85, survival up to banding was calculated as 0.92. 
'The proportion of total pairs breeding at Rochester was 0.66 during the 10-year period 1966-1975. 
3Mean clutch size at Rochester was 2.43 eggs during the 10-year period 1966-1975. 
■^Calculated as mean proportion required to balance life equation. 



The Role of Movements in Population 
Fluctuations 

We concluded earlier that ingress and egress 
contributed significantly to the observed 
changes in horned owl numbers at Rochester 
(Table 3). These changes largely paralleled a 
cyclic fluctuation of Snowshoe Hares, but with 
the owls declining 1 year later. When annual 
recruitment at Rochester is combined with 
estimated post-fledging survival, and ingress and 
egress are assumed to be in balance each year, a 



population fluctuation is generated which peaks 
2 years later than actually observed, and is of 
much lower amplitude (Figure 2). This dif- 
ference between observed and theoretical popu- 
lation trends would hold even if yearlings 
exhibited the same nesting rate as adults (Figure 
2, calculation A). The difference in amplitude 
increases markedly with lower rates of yearling 
nesting, as illustrated in Figure 2 (calculation B) 
where the mean yearling nesting rate was taken 
to be 0.36 that of aduks (i.e., 0.24/0.66; Table 7, 



164 



The Canadian Field-Naturalist 



Vol. 92 



35- 



30- 



OBSERVED 



t^-^m 



CO 25- 



O 

u. 
O 

DC 
LU 

m 



20- 



15- 



10- 




CALCULATED B 



1966 1968 1970 1972 1974 

Figure 2. Comparison of observed and calculated trends in Great Horned Owl numbers at Rochester. Calculated 
trend A is based on observed recruitment of fledged young to the Rochester population, post-fledging survival 
estimated from regional banding data, and the assumption that yearlings and adults breed with the same frequency. 
Calculated trend B assumes that the mean frequency of yearling breeding is 0.36 that of adults (see text). The 
difference between the observed trend and each of the calculated trends is a function of ingress and egress. 



column 5). Amplification of numerical trends on 
the study area was caused by a net ingress of at 
least 25 individuals during the 1966-1971 
increase period, and a net egress of 15 
individuals during the 1972-1975 decline (Table 
3). Egress of between four and nine individuals 
from 1972 to 1973 was primarily responsible for 
the initial population decline. 

If the foregoing analysis of horned owl 
population dynamics at Rochester is generally 
descriptive of Boreal Forest populations, then 
the question naturally arises as to the fate of 
emigrants during decrease years, and the source 
of immigrants during increase years. Dispersal 



rates are higher and dispersal distances longer 
during the population decline as demonstrated 
by band recoveries (Adamcik and Keith 1978). 
The tendency for unusual numbers of northern 
horned owls to occur in southern Canada and 
the United States following Snowshoe Hare 
declines in the Boreal Forest has long been noted 
(Swenk 1937; Spiers 1939), but not quantified. 
Adamcik and Keith (1978) found that 68% of the 
19 band recoveries from dispersing horned owls 
(movements > 25 km) were to the south in years 
of population increase, and a similar 69% of 42 
recoveries in decrease years. On the other hand, 
Houston (1978) examined 209 returns from his 



1978 



Adamcik et al.: Great Horned Owls and Snowshoe Hares 



165 



bandings in Saskatchewan and showed that 35 
of 36 individuals moving over 240 km had 
travelled to the southeast. Thirty-one of the 35 
were recovered in years of population decline. 
Ninety other recoveries of owls which had 
moved 10 to 240 km yielded no evidence of 
directionality. 

Dispersal among the majority of horned owls 
thus seems to be essentially random in all years, 
but during periods of population decline there is 
a cohort which does move well to the south and 
hence out of the Boreal Forest ecosystem. That 
none of Houston's owls which had moved over 
240 km to the southeast were recovered during 
May-August suggests that even these long-range 
dispersers probably return north in spring and 
summer as do wintering Snowy Owls (Keith 
1964). 

We therefore believe that most birds which 
egressed from the Rochester study area settled 
where food resources were sufficient to support 
them, and perhaps in some cases to permit 
nesting. The most likely locations would be on 
agricultural lands lying immediately south of 
the forest and its parkland fringe. Food would 
probably not be critical in the north during any 
summer, and it is quite possible that non-nesting 
individuals wander throughout the forest zone in 
those summers when hares are scarce. We feel 
confident, however, that if present, such non- 
nesters were also non-territorial at Rochester. 

The territorial immigrants which appeared at 
Rochester as the hare population rose toward its 
cyclic peak could have come from a wandering 
cohort of non-territorial individuals wintering 
outside the Boreal Forest, and/ or from ter- 
ritorial residents of agricultural land to the 
south, some of which had earlier dispersed from 
the forest zone when hares had become scarce. 
We think it muchiess likely that the apparent 
immigrants were in fact present all along, and 
only became territorial as hares became in- 
creasingly abundant. 

Territoriality as a Factor Limiting the Great 
Horned Owl Population at Rochester 

Territoriality in avian populations may space 
and/ or limit numbers of individuals (Brown 
1969; Klomp 1972; Newton 1976), and it is well 
documented among breeding populations of 
Great Horned Owls (Baumgartner 1939; Craig- 



head and Craighead 1956, p. 269; Smith 1969). 
Mclnvaille and Keith (1974) felt that horned 
owls at Rochester were spaced but not limited by 
territoriaUty, since between 1967 and 1971 (years 
of hare population increase) the distribution of 
nests remained significantly regular, but the 
density of the territorial pairs rose almost three- 
fold. 

In 1972, however, the density of territorial 
pairs on the Rochester area failed to increase 
(Table 2). Hares were declining at that time but 
still abundant relative to the owls' requirements, 
as evidenced by: (1) 100% of the resident pairs 
producing and incubating a clutch, and (2) food 
biomass supplied daily to tethered young (Table 
6) being similar to that during the two previous 
years. There had been a net ingress (and 
accompanying increase in owl density) in earlier 
years such as 1967 and 1968 when hares were far 
less abundant than in 1972. It therefore seems to 
us that territoriality may have prevented a 
further rise in owl density in spring 1972, and 
thus may have actually begun to limit the study 
area population 1 year earlier when its observed 
density was identical. 

The peak breeding density at Rochester of one 
horned owl pair/ 10.1 km^ was still below that 
reported from some other areas: 1/1.3 km^ in 
Kansas (Baumgartner 1939); 1/6.5 km- in Utah 
(Smith 1969); and 1/7.8 km2 in Wyoming 
(Craighead and Craighead 1956, p. 215). This 
suggests to us that maximum densities are not 
solely determined by an innate territoriality, but 
more likely by territoriality combined with, or 
modified by, food suppUes and perhaps other 
factors in regional environments. 

Acknowledgments 

Financial support was provided by the 
University of Wisconsin, College of Agricultural 
and Life Sciences; the Research Council of 
Alberta; the Canadian Wildlife Service; the 
National Science Foundation (Grants GB-12631 
and GB-33320X); and the Green Tree Garden 
Club, Milwaukee, Wisconsin. 

Literature Cited 

Adamcik, R. S. and L. B. Keith. 1978. Regional move- 
ments and mortality of Great Horned Owls in relation 
to Snowshoe Hare fluctuations. Canadian Field-Natura- 
list 92(3). In press. 



166 



The Canadian Field-Naturalist 



Vol. 92 



Baumgartner, F. M. 1939. Territory and population in the 

great horned owl. Auk 56(3): 274-282. 
Brown, J. L. 1969. Territorial behavior and population 

regulation in birds. Wilson Bulletin 81(3): 293-329. 
Clark, P. J. and F. C. Evans. 1954. Distance to nearest 

neighbor as a measure of spatial relationships in popula- 
tions. Ecology 35(4): 445^53. 
Craighead, J. J. and F. C. Craighead. 1956. Hawks, owls 

and wildlife. Stackpole, Harrisburg. 443 pp. 
Flieg, G. M. and P. R. Meppiel. 1972. An account of trio 

nesting by yearling snowy owls in captivity. Raptor 

Research 6(3): 103. 
Fyfe, R. W. 1976. Status of Canadian raptor populations. 

Canadian Field-Naturalist 90(3): 370-375. 
Henny, C. J. 1972. Great horned owl. /« An analysis of the 

population dynamics of selected avian species. United 

States Department of the Interior, Wildlife Research 

Report 1. 99 pp. 
Hickey, J.J. 1952. Survival studies of banded birds. 

United States Fish and Wildlife Service, Special Scientific 

Report, Wildlife Number 15. 177 pp. 
Houston, C. S. 1971. Brood size of the great horned owl 

in Saskatchewan. Bird Banding 42(2): 103-105. 
Houston, C. S. 1975. Reproductive performance of great 

horned owls in Saskatchewan. Bird Banding 46(4): 

302-304. 
Houston, C. S. 1978. Recoveries of Saskatchewan-banded 

Great Horned Owls. Canadian Field-Naturalist 92(1): 

61-66. 
Keith, L. B. 1964. Territoriality among wintering snowy 

owls. Canadian Field-Naturahst 78(1): 17-24. 
Klomp, H. 1972. Regulation of the size of bird populations 

by means of territorial behavior. Netherlands Journal of 

Zoology 22(4): 456^88. 
Lack, D. 1966. Population studies of birds. Clarendon 

Press, Oxford. 341 pp. 



Luttich, S. N., L. B. Keith, and J. D. Stephenson. 1971. 
Population dynamics of the red-tailed hawk (Buteo 
jamaicensis) at Rochester, Alberta. Auk 88(1): 75-87. 

Mclnvaille, W. B. and L. B. Keith. 1974. Predator-prey 
relations and breeding biology of the Great Horned Owl 
and Red-tailed Hawk in central Alberta. Canadian Field- 
Naturalist 88(1): 1-20. 

Murray, G. A. 1976. Geographic variation in the clutch 
sizes of seven owl species. Auk 93(3): 602-613. 

Newton, \. 1976. Population limitation in diurnal raptors. 
Canadian Field-Naturalist 90(3): 274-300. 

Rusch, D. H., E. C. Meslow, P. D. Doerr, and L. B. Keith. 
1972. Response of great horned owl populations to 
changing prey densities. Journal of Wildlife Manage- 
ment 36(2): 282-296. 

Smith, D. G. 1969. Nesting ecology of the great horned owl 
(Bubo virginianus). In Nesting ecology of raptorial birds 
in central Utah. Brigham Young University Science 
Bulletin Biological Series 10(4): 16-25. 

Southern H. M. 1959. Mortality and population control. 
Ibis 101(3^): 429^36. 

Spiers, J. M. 1939. Fluctuations in numbers of birds in the 
Toronto Region. Auk 56(4): 411^19. 

Stewart, P. A. 1969. Movements, population fluctuations, 
and mortality among great horned owls. Wilson Bulletin 
81(2): 155-162. 

Swenk, M. H. 1937. A study of the distribution and migra- 
tion of the great horned owls in the Missouri Valley 
Region. Nebraska Bird Review 5: 79-105. 

Weller, M. W. 1965. Bursa regression, gonad cycle and 
molt of the great-horned owl. Bird-Banding 36(2): 
102-112. 



Received 25 August 1977 
Accepted 21 December 1977 



Population Size and Structure of Four Sympatric 
Species of Snakes at Amherstburg, Ontario 



W. Freedman and P. M. Catling 



Department of Botany, University of Toronto, Toronto, Ontario M5S lAl 

Freedman, W. and P. M. Catling. 1978. Population size and structure of four sympatric species of snakes at Amherstburg, 
Ontario. Canadian Field-Naturalist 92(2): 167-173. 

Populations of Thamnophis butleri, T. sirtalis sirialis, Storeria dekayi dekayi, and Elaphe vulpina gloydi were studied in an 
abandoned quarry site in extreme southwestern Ontario. Estimates of population size for the 40-ha study area, based on 
various census techniques, are 900 T. butleri, 23 snakes/ ha; 150 T. sirtalis, 4 snakes/ ha; 550 5. dekayi, 14 snakes/ ha; and 
50-120 E. vulpina. 1.3-3.2 snakes/ ha. Thamnophis sirialis and S. (^eA:or/ were confined to small subsections ofthe main study 
area and within their actual area of occurrence had densities of 20 and 70 snakes/ ha respectively. The relatively high density of 
snakes in the study area is thought to be related to abundant food, cover and denning sites. Sex ratios and size frequency 
distributions are described for all species, and brood size and percentage of gravid females are given for T. butleri. For all 
species, the proportion of young ofthe previous year was small, and the size distributions were strongly skewed toward adult 
size classes. 

Key Words: Thamnophis butleri, Thamnophis sirtalis sirtalis, Storeria dekayi dekayi, Elaphe vulpina gloydi, population size, 
sex ratios, size classes, population densities, brood size, Amherstburg, southwestern Ontario. 



Although some quaUtative assessments have 
been made concerning changes in status of 
Canadian snakes (i.e., Logier 1957; Cook 1970; 
Rivard 1976; Pendlebury 1977; unpublished 
manuscripts by C. A. Campbell for Ontario 
Ministry of Natural Resources 1975, University 
of Western Ontario 1977, and Canadian Wildlife 
Service 1977), few quantitative estimates of 
population size or structure now exist. The only 
published estimates of Canadian snake popula- 
tions known to the authors of this paper are for 
certain dense local aggregations ofthe Red-sided 
Garter Snake {Thamnophis sirtalis parietalis) 
utilizing karst hibernacula in the Interlake 
district of Manitoba (Gregory 1974, 1977; 
Aleksiuk 1977). For the 14 taxa of snakes 
(including 10 species), represented as rare or 
endangered in Canada by Cook (1970), there are 
no published estimates of size of local popula- 
tions. Such quantitative estimates are important 
to the conservation of animal populations, 
since before effective management programs or 
protective measures can be undertaken, geo- 
graphical distributions, demographic character- 
istics, and various other aut-and syn-ecological 
relationships must be described, so that action 
can be based on sound knowledge of the 
organisms concerned. 

The purpose of the present report is to 
describe the population sizes and structure of 



four sympatric species of snakes at a site near 
Amherstburg, Ontario. Two of these species, the 
Butler's Garter Snake ( Thamnophis butleri) and 
the Eastern Fox Snake {Elaphe vulpina gloydi), 
have been considered as rare or endangered in 
Canada by Cook (1970). The other two species, 
the Eastern Garter Snake {Thamnophis sirtalis 
sirtalis) and the Northern Brown Snake {Stor- 
eria dekayi dekayi), are widespread and com- 
mon but are also dealt with in this study because 
little demographic data exist for Canadian 
populations of these species, and because inter- 
actions may occur between them and the two less 
common species with which they are sympatric. 
Other aspects ofthe ecology of sympatric snakes 
at the Amherstburg site, such as movements and 
distribution, are under study. 

Study Area 

Located approximately 2.4 km northeast of 
Amherstburg, 42°07'N and 83°05'W, in Ander- 
don Township of Essex County, Ontario, the- 
study area is approximately 40 ha in extent. The 
substrates are calcareous (pH 7.6 7.8) through- 
out the area and vary from limestone pavement 
and coarse limey gravel to fine-textured cal- 
careous clay-loam. The western portion of this 
area is comprised of an old limestone quarry that 
is relatively high, rocky, and irregular in 
topography. The lower eastern portion includes 
abandoned industrial and agricultural lands. 



167 



168 



The Canadian Field-Naturalist 



Vol. 92 



The quarry has been abandoned for at least 15 
years, and the agricultural and industrial sectors 
for 5 years. Cottonwood {Populus deltoides), 
hawthorn {Crategus mollis), dogwood (Cornw5 
drummondii), sumacs {Rhus typhina and R. 
glabra), and choke cherry (Prunus virginiana) 
have partially colonized the landscape, but 
extensive open areas exist, dominated in the 
drier parts by Poa compressa and elsewhere by 
other grasses and forbs {Poa pratensis, Dactylis 
glomerata, Phleum pratense, Festuca pratensis, 
Daucus carota, Solidago nemoralis, Melilotus 
alba, Fragaria virginiana, Pastinaca saliva, etc.). 
Periodically wet areas are dominated by Puc- 
cinellia distans while some permanently wet 
areas in the eastern part of the study have dense 
stands of cattail {Typha latifolia and T. 
angustifolia). Extensive rocky barren and semi- 
barren areas occur throughout the study area, 
and the cover of non-wooded areas varies from 
low (20 cm) and sparse to tall (1 m) and dense. 
Such variation frequently occurs over distances 
of only a few metres. 

The study area is bounded on the west by the 
settling pools and service roads of Allied 
Chemicals Ltd., on the north by a railway and 
agricultural lands, on the east by oak-hickory 
woods {Quercus alba, Q. macrocarpa, Q. 
borealis, Carya ovata) and swampy lowlands, 
and on the south by agricultural lands. Since no 
snakes were found in these peripheral areas 
(comprising a larger study area of 64 ha), it 
appears that our 40-ha study area represents a 
more or less isolated "island" of optimal snake 
habitat. 

Much of the site has been used as an 
unmanaged garbage dump by local residents, 
and numerous small fires, started to burn trash, 
have helped to maintain open grasslands. Litter 
from derelict buildings is common in the eastern 
section and piles of debris and rubble are 
characteristic of at least half of the area. Trails 
made by all-terrain vehicles and trail bikes are 
much in evidence in the quarry section. 

Methods 

All data presented here were gathered during a 
series of visits to the study area during the spring 
and summer of 1976. Some additional data 
relevant to Eastern Fox Snakes, collected in the 
spring of 1977, are also included. During the 



initial precensus and on each of the four census 
dates, sub-sections of the study tract were 
walked in a pre-determined order and virtually 
all snakes seen (including many hiding under 
cover) were captured for examination. Un- 
marked individuals were marked by clipping 
scales from the dorsal scale rows according to a 
numbering scheme that made it possible to 
distinguish individuals. This technique of mark- 
ing is quite simple, and requires simpler surgery 
than the method of Blanchard and Finster 
(1933), who advocate the removal of complete 
subcaudal scutes, and yields more easily rec- 
ognized marks than the method of Spellerburg 
(1977), who advocates the partial removal of 
subcaudal scutes. Our technique appeared to 
cause no discomfort to the snakes, and in captive 
Eastern Garter Snakes the marks were healed 
within 2 wk, but were clearly visible at the time 
of their release 1 V2 yr later. In addition, for all 
snakes captured and marked, the sex (deter- 
mined by post-cloacal hemipenal distention in 
males), total length, gravidity (based on pro- 
nounced pre-cloacal body distention), color 
variation, characteristic markings, and various 
ecological data were recorded. Snakes born in 
1976 were found only in the late summer 
censuses and were too small to be marked 
without possible injury, and are not included in 
the population size estimates or in the calcula- 
tions of size distributions or sex ratios. 

Population size estimates were made using the 
Petersen mark-recapture method within the 
context of multiple censusing. Statistically, the 
method requires that (1) the population is 
constant, with no mortality or recruitment 
during the experiment, (2) no immigration or 
emigration occurs, and (3) certain statistical 
assumptions are met concerning the randomness 
of capture and mixing of marked and unmarked 
individuals. Although these requirements are 
rarely fully satisfied in studies of animal 
populations, the method has nevertheless been 
effectively utilized in estimating local popula- 
tions of snakes in the United States (Carpenter 
1952; Fitch 1960, 1963, 1964, 1965. 1975). The 
technique is described in detail in the above 
references, and by Ricker (1975) and Smith 
(1974). 

For each of the four census dates, a Petersen 
estimate of the population size was calculated 



1978 



FREEDMAN and CATLING: SNAKES, AMHERSTBURG, ONTARIO 



169 



for three of the four species of snake. In addition, 
separate population estimates were made using 
four different multiple census calculations (i.e., 
the Schumacher, Schnabel, modified Schnabel, 
and Mean of Petersen Estimates). Ninety-five 
percent confidence intervals were also calculated 
for each population estimate. All of these 
calculations, and their relevant statistical as- 
sumptions, are summarized in detail by Ricker 
(1975). 

Unfortunately, there were no recaptures of 
Eastern Fox Snakes during the 1976 censuses, 
and only one recapture was observed during the 
spring of 1977. Assuming that all Eastern Fox 
Snakes marked on the five 1976 sampling dates 
comprised a collective precensus, one can 
calculate a Petersen population estimate based 
on the single 1977 recapture. But an indirect 
estimate of the Eastern Fox Snake population 
can also be calculated, as follows. From Table 1, 
it may be calculated that a mean of 50 different 
Butler's Garter Snakes were captured on each of 
the five census dates, i.e., (61 + 69 + 49 + 48 + 
23)/5 = 50. The mean estimate of population size 
for this species is given in Table 2 as 896. Thus, 
the probability of capturing a particular snake 
during any particular one of the census dates 
may be estimated as 50/896 = 0.0558. This 
probability is based on the same assumptions 
stated previously for the mark-recapture method 
in general. By similar means, the probability of 
capture for Eastern Garter Snakes is established 
as 14.4/158 = 0.0911, and for Northern Brown 
Snakes as 20.4/545 = 0.0374. The mean of these 
three estimates is (0.0558 + 0.0911 +0.0374)/ 3 



= 0.0614. Assuming that the probability of 
capturing a particular Eastern Fox Snake is 
roughly the same as that for the other species, we 
can apply the average probability of capture 
(0.0614) to Eastern Fox Snakes. This is done by 
multiplying the average number captured by the 
inverse of this probability in order to calculate a 
first-order approximation of the population 
size. 

Observations and Discussion 

Petersen estimates of the population sizes of 
three of the four species of snake on each of the 
four census dates are summarized in Table 1. 
The large standard errors are mainly due to 
relatively low recapture percentages. 

Table 2 gives the multiple census population 
estimates for three species of snake. These four 
population estimates each involve somewhat 
different statistical assumptions and have dif- 
ferent modes of calculation. Each calculation is 
based on an integration of the data from all four 
census dates presented in Table 1. Where popula- 
tion estimates at various dates are quite different 
from each other and the number of censuses in 
the multiple census is low (both of which are 
factors in our data), the 95% confidence interval 
can be quite large. High variation in population 
estimates of snake populations have also been 
reported in other snake census studies (i.e. Fitch 
1960, 1963, 1975; Gregory 1974, 1977). Fitch 
(1975) considered this high variability to be an 
inescapable feature of mark-recapture censuses 
involving snakes because of low recapture 
success and the secretive behavior of most 



Table 1 — Population estimates (Petersen calculation) for four species of snakes on four 1976 census dates. H 
handled; R = number recaptured; Est. - population estimate 



number 





Butler's Garter 


Eastern Garter 


Northern Brown 




Eastern Fox 




Snake 




Snake 




Snake 




Snake* 




( Thamnophis 


( Thamnophis 




i Store ria 




( Elaphe 




huileri) 


sirtahs) 




clekayi) 




vulpina) 


Date 


H R Est. 


SE 


H R Est. SE 


H 


R Est. SE 


H 


R Est. SE 


14 May** 


61 — — 





15 - - — 


15 





3 




30 May 


69 6 702 


±274 


14 1 210 ±56 


25 


1 375 ±367 


6 


— — 


15 June 


49 6 1013 


±387 


15 4 105 ±45 


22 


3 286 ±153 


3 


— — 


10 July 


48 5 1603 


±679 


16 3 208 ±108 


33 


2 957 ±656 


2 


— — 


24 July 


23 9 537 


±140 


12 4 156 ±64 


7 


1 623 ±577 


2 


— — 


Mean + SD 


964 


±470 


170 ±50 




560 ±300 




— — 



*See text for Petersen estimate based on 1977 recapture. 
**Precensus date. 



170 



The Canadian Field-Naturalist 



Vol. 92 



Table 2— Multiple census population estimates for three species of snakes. Four methods of calculating population size are 
summarized, based on four 1976 census dates 





Butler's 


Garter Snake 


Eastern 


Garter Snake 


Northern 


Brown Snake 


Method of population 
size estimate 


( Thamnophis butleri) 


( Thamnophis sirtalis) 


(Storeria dekayi) 


Population 


95% confidence 


Population 


95% confidence 


Population 


95% confidence 


calculation 


size 




interval 


size 


interval 


size 


interval 


Schumacher 


872 




220 to 1922 


159 


63 to 484 


610 


96 to 1229 


Schnable 


890 




220 to 2317 


157 


63 to 327 


539 


96 to 987 


Modified Schnabel 


857 




593 to 1285 


144 


85 to 268 


471 


251 to 943 


Petersen mean 


964 




220 to 1904 


170 


70 to 270 


560 


96 to 1160 


Mean of four different 
















estimates 


896 






158 




545 





snakes. He nevertheless noted that, although the 
mark-recapture method does not provide a 
precise measure of population size, it does 
provide better information in most cases than 
direct or relative (i.e., snakes seen or caught per 
man-hour) counts, and at least indicates the 
order of magnitude of the population size. 

Table 2 shows that the approximate popula- 
tion size of Butler's Garter Snake is 900 
(23 snakes/ ha), Eastern Garter Snake 150 
(4 snakes/ ha), and Northern Brown Snake 550 
(14 snakes/ ha). But both Eastern Garter Snakes 
and Northern Brown Snakes were localized in 
the mesic to wet eastern parts of our study area 
(approximately 7-8 ha), so that the effective 
population densities of these species within their 
areas of occurrence are closer to 20 snakes/ ha 
and 70 snakes/ ha, respectively. 

The Eastern Fox Snake population can only 
be crudely estimated by the mark-recapture 
method because there was only one recapture. 
The Petersen population estimate based on 
this recapture is 128 snakes (SE = 120, den- 
sity - 3.2 snakes/ ha). The large standard error is 
largely a result of the single recapture. Rivard 
(1976) also noted very low recapture success with 
Eastern Fox Snakes in a study at Point Pelee, 
Ontario. An indirect first-order approximation 
of the Eastern Fox Snake population (based on 
an average probability of capture of the other 
three species sympatric at this site, and the 
assumption that the Eastern Fox Snakes exhibit 
a similar probability) is 52 (1.3 snakes/ ha). 

Carpenter (1952) calculated densities of 24.2 
and 7.2 snakes/ ha for Eastern Garter Snakes 
and Butler's Garter Snakes, respectively, at a site 
in Michigan where they were sympatric, while 



Fitch (1965) observed densities of Eastern 
Garter Snakes that ranged from 2.2 to 
10.9 snakes/ha from 1956 to 1963 at a site 
in Kansas. Gregory (1977) calculated popula- 
tion sizes of Red-sided Garter Snakes at an 
intensively utilized denning site in Manitoba 
that ranged from 2056 to 5347 at various times 
from 1969 to 1973. He did not express any of his 
populations on a density basis. All of these 
authors considered their study sites to be 
areas of locally high snake populations. R. J. 
Planck (1977, unpublished report to Depart- 
ment of Supply and Services, Ottawa) reported 
total populations of Butler's Garter Snakes at a 
site (apparently 16 ha) near the Windsor airport, 
Ontario which varied from 55 to 1414 
(mean = 455, SD = 457), based on five sampling 
dates in 1976. 

The calculated Eastern Fox Snake densities at 
our site can only be compared to densities of the 
congeneric Black Rat Snake {Elaphe obsoleta) 
studied in Kansas by Fitch (1964), where 
densities of 4.2 snakes/ ha were calculated dur- 
ing the period of relatively high abundance 
following the seasonal appearance of young 
snakes, while densities of 2.1 snakes/ ha were 
noted at other times of the year. Fitch consider- 
ed his study locale to be an area of high density 
for this species. We are unaware of any 
published population estimates to which our 
data on Northern Brown Snake can be com- 
pared. 

The relative abundance of snakes at the 
Amherstburg site is believed due to some 
combination of (1) good cover provided by the 
numerous flat boards, pieces of metal, dis- 
carded mattresses, and miscellaneous other 



1978 



FREEDMAN and CATLING: SNAKES, AMHERSTBURG, ONTARIO 



171 



scattered items that were found throughout the 
study area; (2) the apparent abundance of 
suitable food resources (i.e., an abundance of 
earthworms, amphibians, and small mammals); 
and (3) the probable presence of hibernacula in 
rocky parts of the quarry, in numerous piles of 
debris, or in foundations of derelict buildings. 
Table 3 summarizes data on sex ratios and 
total length. The ratio of males to females in 
Butler's Garter Snake and the Eastern Garter 
Snake approximates 1, while for the Northern 
Brown Snake we found twice as many females as 

A) Thamnophis butleri {n = 224) 



males, and for the Eastern Fox Snake there were 
approximately twice as many males as females. 
Fitch (1965) found the proportion of male 
snakes to be 0.53 for Eastern Garter Snakes at a 
site in Kansas, and he noted that this ratio varied 
seasonally, with relatively more males than 
females being present in his fall samples relative 
to his spring-summer samples. Gregory (1977) 
found the proportion of males in Red-sided 
Garter Snakes ranged from 0.52 to 0.65 at a site 
in Manitoba. Planck {op. cit.) found the propor- 
tion of males of Eastern Garter Snakes and 



10 




20 



1 1 



Thamnophis sirtolis (n=63) 



i I 




C) Storeria dekayi ( n = 96) 



C?(^$$ 




I I — r-i— 1 — p-i 

10 20 30 40 50 60 70 80 

TOTAL BODY LENGTH (cm) 
Figure 1. Size frequency distributions for three species of snakes from the Amherstburg, Ontario study site. The mean sizes 
of males and females are indicated. A, Butler's Garter Snake ( Thamnophis hutleh); B, Eastern Garter Snake ( Thamnophis 
sirtaUs sirtahs): C, Northern Brown Snake {Storeria dekayi dekayi). 



172 



The Canadian Field-Naturalist 



Vol. 92 



Table 3 — Sex ratios and mean total length of four species of snakes at the Amhertsburg study site 



Species 





Proportion 


Mean length. 


Mean length. 


No. examined 


of males ± SE 


male (cm ± SD) 


female (cm ± SD) 


220 


*0.555± 0.034 


36 ±7 


40 ±7 


63 


*0.495 ± 0.063 


52 ± 12 


56 ± 13 


96 


0.365 ± 0.049 


29 ±4 


33 ±6 


28 


0.680 ±0.089 


102 ±20 


110 ±25 



Butler's Garter Snake 

{Thamnophis bulleri) 
Eastern Garter Snake 

( Thamnophis sirtalis) 
Northern Brown Snake 

(Storeria dekayi) 
Eastern Fox Snake 

{Elaphe vulpina) 



Not significantly different from male: female ratio of 1.0 (P< 0.05) 



Butler's Garter Snake from sites in southwestern 
Ontario to be 0.38 and 0.45, respectively. Rivard 
(1976) found male proportions for Eastern Fox 
Snakes ranging from 0.41 to 0.86, with an overall 
proportion of 0.51 at a number of sites in 
southwestern Ontario. 

Mean total length of females was slightly 
longer than that of males for all species, 
although there was, of course, very considerable 
overlap between the two sexes, and variation 
was large. Figure 1 shows that the length- 
frequency distributions for three species are 
skewed toward adult sizes. For all species, the 
proportion of young born the previous year in 
the population samples was quite small (less 
than 5%), except for the late summer censuses of 
Butler's Garter Snake, when up to 30% of the 
individuals handled were recently-born young. 
The latter observation of low proportion of 
yearlings in the spring-summer censuses could 
have resulted from some combination- of high 
infant mortality, or the possibility that yearlings 
were proportionately under-represented in the 
census owing to behavioral difference between 
yearling and adult snakes. Carpenter (1952) 
made similar observations on this matter for 
Eastern Garter Snakes and Butler's Garter 
Snakes at a site in Michigan. 

In each of the three common species handled 
in our study, about 65% of the adult females 
(more than one year old) were obviously gravid. 

Brood size was determined for the Butler's 
Garter Snake. Six females that were retained in 
captivity had broods of 4, 7, 9, 10, 10, and 11. 
The largest broods were from females with total 
lengths of 54.5 cm (11 young), 54.5 cm (10 
young), and 46.0 cm (10 young). Wright and 



Wright (1957) cite brood size of Butler's Garter 
Snake ranging from 4 to 16, with an average of 9. 
The proportion of stillborn young or young with 
rapidly fatal birth defects was 5%. 

Acknowledgments 

We thank F. Cook of the National Museum, 
Ottawa, C. Campbell of Waterloo, Ontario, 
P. T. Gregory of the University of Victoria, and 
H. Regier of the University of Toronto for their 
critical reading of the manuscript and their 
helpful suggestions. The field assistance of S. 
McKay and K. Mcintosh is gratefully ac- 
knowledged. 

Literature Cited 

Aleksiuk, M. 1977. Sources of mortality in concentrated 
Garter Snake populations. Canadian Field-Naturalist 91: 
70-72. 

Blanchard, F. N. and E. B. Finster. 1933. A method of 
marking live snakes for future recognition, with a dis- 
cussion of some problems and results. Ecology 14: 
334-347. 

Carpenter, C. C. 1952. Comparative ecology of the com- 
mon garter snakes ( Thamnophis siriah's), the ribbon snake 
{Thamnophis sauritus), and Butler's garter snake (Tham- 
nophis butleri) in mixed populations. Ecological Mono- 
graphs 22: 235-258. 

Cook, F. R. 1970. Rare or endangered Canadian reptiles 
and amphibians. Canadian Field-Naturalist 84: 9-16. 

Fitch, H. S. 1960. Autecology of the Copperhead. Museum 
of Natural History, University of Kansas Publications 13: 
85-228. 

Fitch, H. S. 1963. Natural history of the Racer (Cohiber 
constrictor). Museum of Natural History, University of 
Kansas Publications 15: 351-468. 

Fitch, H. S. 1964. Natural history of the Black Rat Snake 
{Elaphe obsoleta) in Kansas. Copeia 1964: 649-659. 

Fitch, H. S. 1965. An ecological study of the Garter Snake 
{Thamnophis sirtalis). Museum of Natural History, Uni- 
versity of Kansas Publications 15: 493-564. 



1978 



FREEDMAN and CATLING: SNAKES, AMHERSTBURG, ONTARIO 



173 



Fitch, H. S. 1975. A demographic study of the Ringneck 
Snake {Diadophis punctatus) in Kansas. University of 
Kansas Museum of Natural History, Miscellaneous 
Publications 62. 53 pp. 

Gregory, P. T. 1974. Patterns of spring emergence of the 
Red-sided Garter Snake (Thamnophis sirtalis parietalis) 
in the Interlake region of Manitoba. Canadian Journal of 
Zoology 52: 1063-1069. 

Gregory, P. T. 1977. Life history parameters of the Red- 
sided Garter Snake (Thamnophis sirtahs parietalis) in an 
extreme environment, the Interlake region of Manitoba. 
National Museums of Canada, Publications in Zoology 
Number 13. 44 pp. 

Logier, E. B. S. 1957. Changes in the amphibian and 
reptilian fauna of Ontario. In Changes in the fauna of 
Ontario. Edited by F. A. Urquhart. University of Toronto 
Press, Toronto, pp. 13-18. 

Pendlebury, G. B. 1977. Distribution and abundance of the 
Prairie Rattlesnake, Crotalis viridis viridis, in Canada. 



Canadian Field-Naturalist 91: 122-129. 
Ricker, W. E. 1975. Computation and interpretation of 

biological statistics of fish. Fisheries Research Board of 

Canada, Bulletin 191. 382 pp. 
Rivard, D. H. 1976. The biology and conservation of 

Eastern Fox Snakes (Elaphe vulpina gloydi Conant). 

M.Sc. thesis, Carleton University, Ottawa. 64 pp. 
Smith, R. L. 1974. Ecology and field biology. 2nd edition. 

Harper and Row, New York. 850 pp. 
Spellerberg, C. G. 1977. Marking live snakes for identifica- 
tion of individuals in population studies. Journal of 

Applied Ecology 14: 137-138. 
Wright, A. H. and A. A. Wright. 1957. Handbook of 

snakes. 2 volumes. Comstock Publishers, New York. 

1107 pp. 



Received 23 September 1977 
Accepted 7 December 1977 



Distribution of Salamanders of the 
Ambystoma jeffersonianum Complex in Ontario 



Wayne F. Weller,' W. Gary SprulesJ and Terry P. Lamarre2 

'Department of Zoology, Erindale College, University of Toronto, Mississauga, Ontario L5L 1C6 
-Ontario Ministry of Natural Resources, Box 309, Sioux Lookout, Ontario POV 2T0 

Weller, W. F., W. G. Sprules, and T. P. Lamarre. 1978. Distribution of salamanders of the Ambystoma jeffersonianum 
complex in Ontario. Canadian Field-Naturalist 92(2): 174-181. 

New distributional data on the four species of salamanders of the Ambystoma jeffersonianum complex in Ontario show 
that the ranges of /4. tremblayi, A. platineum. and A. jeffersonianum are more extensive than had previously been known. 
Bruce, Brant, Lincoln, and Russell Counties and Muskoka District are added to the previous range of A. tremblayi; A. 
platineum is newly reported from Wentworth, Halton, York, and Northumberland Counties as is A. jeffersonianum from 
Wentworth and Halton Counties. The two diploid species, A. laterale and A. jeffersonianum, occupy different habitats and 
are almost always allopatric. One possible case of diploid hybridization is discussed. 

Key Words: Ambystoma jeffersonianum complex, range extensions, sympatric distributions, morphology, habitat 
descriptions, museum specimens. 



The Ambystoma jeffersonianum complex 
consists of four salamander species (Uzzell 
1964): two dioecious, diploid {In - 28) forms, A. 
laterale and A. jeffersonianum; and two essen- 
tially all-female, triploid (3/? = 42) forms, A. 
tremblayi and A. platineum. The triploids arose 
by hybridization of the diploid forms (Uzzell and 
Goldblatt 1967) and, as presently understood, 
reproduce gynogenetically. Ambystoma trem- 
blayi usually mates with A. laterale males as does 
A. platineum with A. jeffersonianum males. 

The history of the nomenclature of this 
complex has been presented by Uzzell (1964, 
1967a, b. c, d). whose interpretation we follow 
here. 

Although all four species are known from 
Ontario, much of the data is unpublished and 
many museum specimens have been incorrectly 
identified. We here draw together all existing 
data and re-examine museum specimens to 
present a synthesis of the taxonomic and 
distributional status of this complex in Ontario. 
The literature concerning the habitats of the 
diploid species of this complex is reviewed, and 
those from where Ontario specimens were taken 
are described. 

Materials and Methods 

Salamanders were examined from the 
National Museum of Natural History, Washing- 
ton (USNM), the Royal Ontario Museum, 
Toronto (ROM), and the National Museum of 
Natural Sciences. Ottawa (NMC). Living in- 
dividuals, collected from eight localities in 
southern Ontario in March and April 



1974-1976, were deposited in the herpetological 
collection of the National Museum of Natural 
Sciences, Ottawa. 

Snout-vent length (tip of snout to posterior 
angle of vent), total length, and internarial width 
(distance between external nares) were recorded 
for each specimen. To determine ploidy of living 
specimens, blood obtained by digit amputation 
was spread in a thin film on glass slides and 
allowed to dry. Erythrocyte nuclear area was 
determined by planimeter tracings of camera 
lucida drawings from these preparations, and 
longest nuclear diameter was measured using an 
ocular micrometer. The ploidy of a subsample of 
specimens, determined by the electrophoretic 
patterns of the blood plasma proteins, was used 
to establish an empirical relation between 
nuclear diameter and ploidy (Table 1). There- 
after a sequential sampling analysis of longest 
nuclear diameter (Wilbur 1976) was used to 
determine the ploidy of individual specimens. 
Because the nuclear membrane shrank less than 
the cell membrane during slide preparation, 
nuclear area.was considered a better correlate of 
ploidy than was erythrocyte area. To permit 
comparisons with published results, however, 
erythrocyte area was calculated for the speci- 
mens using a regression relationship with 
nuclear area established from the subsample of 
animals. 

Results 

Ambystoma laterale 

This species is widely distributed in Ontario 
from the international border to Favourable 



174 



1978 



Weller et al.: Ambystoma jeffersonianum Complex, Ontario 



175 



Table 1 — Confidence limits of erythrocyte nuclear diam- 
eters using a sequential sampling procedure for distinguish- 
ing diploid and triploid salamanders of the A. jeffer- 
sonianum complex. The identification of a diploid or a 
triploid specimen can be made with 99% confidence when the 
cumulative sum of nuclear diameters is either less than, or 
greater than the confidence limits, respectively. These values 
are presented herein since those of Wilbur (1976) do not 
satisfactorily distinguish diploid and triploid Ontario 
salamanders of this complex 

Maximum cumulative Minimum cumulative 
sum of longest nuclear sum of longest nuclear 
Number diameters (;um) for diameters {y.m) for 

of diploids A. laterale triploids A. tremblayi 

cells and A. jeffersonianum and A. platineum 



13 

26 

39 

,53 

66 

79 

92 

105 

118 

131 

144 

157 

170 

183 

196 



19 

32 

45 

58 

71 

84 

97 

111 

124 

137 

150 

163 

176 

189 

202 



Lake, Lake Nipigon, and James Bay in the north 
(Uzzell 1967b). Males of this species were 
identified from Brant and Carleton County 
museum specimens, and from Halton County 
living specimens on the basis of morphology and 
pigmentation {cf., Weller and Sprules 1976). 

Ambystoma tremb lay ' i 

This species has been reported in Ontario only 
from Halton County (Menzel and Goellner 
1976), Frontenac County (Uzzell 1964), and 
Carleton County (Uzzell 1967d), shown by the 
hollow circles, west to east, respectively, in 
Figure 1. 

We have examined seven Ontario sala- 
manders of this complex that are in the U.S. 
National Museum. USNM 10830 is represented 
by one female from "Lucknow, Ontario," Bruce 
County (Figure 1, westernmost solid circle) that 
was identified as A. j. jeffersonianum (Cope 
1889). It seems certain, however, that this 
specimen is triploid because its snout width falls 
between that of A. jeffersonianum and A. 



laterale females (Figure 2). Furthermore, the 
coloration and presence of the typical A. 
laterale-like spotting on the tail suggest that it 
is A. tremblayi rather than A. platineum. 

USNM 4690 is represented by two specimens, 
not one as indicated by Cope (1889), that have 
been identified as A. j. jeffersonianum from ''St. 
Catharine's, Canada." Both are female. One 
contains enlarged ovarian eggs; the other is 
immature, and cannot be identified on the basis 
of morphology. Cope ( 1 889) identified the larger 
female (presumably) listed under USNM 4690 as 
A. j. jeffersonianum and four females from the 
same locality, two under USNM 4822 (not 4022 
as published) and two under USNM 14471, as ^. 
/. fuscum. With the exception of one individual 
under USNM 4822, all contain enlarged ovarian 
eggs. Because the two largest sexually mature 
individuals have a shorter snout-vent length 
than the shortest sexually mature A. platineum 
yet examined (73 mm, Uzzell 1967c; 69 mm, 
Weller, unpublished) and a wider snout than A. 
laterale females (Figure 2), it seems likely that 
they are examples of A. tremblayi. The other 
three mature specimens from Lincoln County 
seem also to be A. tremblayi rather than A. 
laterale on the basis of the relatively wide snout. 

The preserved females from Brant, Carleton, 
and Russell Counties had museum labels iden- 
tifying them as A. laterale and A. tremblayi. 
Those that have a longer snout-vent length than 
A. laterale have generally proportionally nar- 
rower snouts than A. platineum (Figure 2). The 
presence of A. laterale males in these popula- 
tions reinforces the taxonomic status of these 
females as A. tremblayi. 

Living individuals of A. tremblayi were 
collected from Muskoka District (Figure 1, solid 
circle east of Georgian Bay) and Halton County 
(Figure 3A) in southern Ontario. These, and the 
museum specimens, are typical of the species in 
relative tail length (Figure 4A). There appears to 
be no variation in erythrocyte size between A. 
tremblayi from Ontario and those from southern 
populations (Figure 4B). 

These records extend the distribution of A. 
tremblayi to include five new counties or 
districts (Bruce, Brant, Lincoln, Muskoka, and 
Russell) and eight new localities in Ontario. The 
taxonomic status of USNM 10830 and of the 
mature female under USNM 4690 has been 



176 



The Canadian Field-Naturalist 



Vol. 92 




Figure \. Distributional records of salamanders of the Amhysionw jeffersonianum complex in southern Ontario. Hollow 
symbols represent published records, solid symbols unpublished records. Circles refer to A. tremblayi, diamonds to 
A. platineitm, and the square to A. jeffersonianum. Note the combination symbol of a hollow square and solid 
diamond. 



changed from 
tremblayi, and 
14471, from A. 



A.J. Jeffersonianum to A. 
of USNM 4822 and USNM 
j. fuscum to A. tremblayi. 



Ambystoma platineum 

This species has been conclusively identified 
only from Waterloo County (C. A. Campbell, 
B. W. Menzel, and P. Pratt, unpublished data) 
and Peel County (W. F. Weller and B. W. 
Menzel, unpublished data) in Ontario (Figure 1, 
westernmost solid diamond and combination 
symbol, respectively). 

We have examined four females of the 
complex from York County, "near Toronto" 
(ROM 3714-17), and one female from North- 
umberland County (ROM 122) that have 
museum labels identifying them as A. Jef- 
fersonianum (Figure 1, middle and eastern 
solid diamonds). All five specimens have 
females and intermediate between A. tremblayi 
and A. Jeffersonianum females in snout width 
(Figure 2). It seems almost certain that they are 
examples of A. platineum. 

Living specimens were collected from five 
localities in Peel, Halton, and Wentworth 



Counties (Figure 3A, solid circles). These speci- 
mens possess slightly longer tails and larger 
erythrocytes (Figure 4) than salamanders oi A. 
platineum from southern populations. 

Cope (1889) reported one record as A.j. 
platineum from "Moose River, British 
America," but the specimen (USNM 5368) has 
been lost or destroyed (R. I. Crombie, personal 
communication). In view of the known distribu- 
tion oi A. platineum summarized in this paper, it 
seems almost certain that USNM 5368 from the 
James Bay region of Ontario was not a specimen 
of A. platineum. 

The results extend the distribution of A. plati- 
neum to include four new counties (Wentworth, 
Halton, York, and Northumberland) and six new 
localities in Ontario. The taxonomic status of 
ROM 3714-17 and ROM 122 has been changed 
from A. Jeffersonianum to A. platineum. 

Ambystoma Jeffersonianum 

Only one record from Canada, based upon 
male specimens from Peel County, Ontario 
(Weller and Sprules 1976), has been published 
(Figure 1, combination symbol). 



1978 



Weller et al.: Ambystoma jeffersonianum Complex, Ontario 



177 



6.2 



5.8- 



5.4- 



5.0 



i4.6 



4.2 ■ 



E 3.8 



3.4 



3.0- 



2.6- 



I Bruce Co. y^ 

▼ Lincoln Co. 

A Brant Co. 

:: Corleton & Russell Co 

9 York Co., near Toront 

^ Northumberland Co. 

I I Middlesex Co. 

A York Co. 

V Findlay,Ohio 

O Victoria Co. 

(5754 




A. trem 



A. laterale 



50 



60 



70 



80 



90 



100 



Snout-vent Length (mm) 
Figure 2. Relationship of internarial width to snout-vent length for preserved females of the A. Jeffersonianum complex 
from museum collections. The margins of the clouds of points for the four species are based upon females of known 
identity presented in this paper and in Uzzell ( 1964). Solid symbols represent specimens for which the identit\' could 
be deduced; hollow symbols, those for which the identity could not be made. Numbers associated with hollow symbols 
refer to ROM catalogue numbers. 



Females of this species were collected from 
five localities in Wentworth, Halton, and Peel 
Counties (Figure 3A, solid circles). They have 
slightly longer tails (Figure 4 A) and larger 
erythrocytes than female A. Jeffersonianum 
from southern populations (Figure 4B). 

Males were collected from four localities in 
Wentworth, Halton, and Peel Counties (Figure 
3B). They have considerably longer tails than do 
males from southern populations; the erythro- 
cytes, however, are typical of diploids in size 
(Figure 4B). No triploid males were identified 
among Ontario specimens. 

The distribution of .4. Jeffersonianum in 
Ontario is thus extended to include two new 



counties (Wentworth and Halton) and four new 
localities. 

The precise taxonomic status of several 
Ontario females of this complex in the Royal 
Ontario Museum identified as A. Jeffersoni- 
anum cannot be determined with certainty. 
Three specimens (ROM 1472, 1473. and 1474) 
are from Middlesex County, five (ROM 54, 55, 
1015. 4000. and 5006) are'from York County, 
and one (ROM 5754) is from Victoria County. 
On the basis of snout width alone, it is tempting 
to assign ROM 1472 either to A. laterale or A. 
tremblayi. and ROM 55 to either A. Jeffer- 
sonianum or A. platineum (Figure 2). It is 
almost certain, however, that, except for ROM 



178 



The Canadian Field-Naturalist 



Vol. 92 



-A 


e6\ 


-^-^"""^ 44- 


\ 


<^# 




^ 


> 


/ ONT. 


\ 


, • 


v^__ 


/a 10 
/ ' ' ' 


^v^ km 



-B 


80\ 


^— r — 44- 


V 


<^ • 




-i 


Is \ 


/ ONT. 


\ 


• 


>- 

1^ 10 

/ ' ' ' 


\(^ km 



Figure 3. Distributional records for salamanders of the A. jeffersonianum complex in 1, Peel; 2, Halton; and 3, Wentworth 
Counties of Ontario from collections made by the authors. (A) Females: hollow circles, A. iremblayi: solid circles, 
A. Jeffersonianum and A. plalineum. (B) A. jeffersonianum males. 



4000, the remaining specimens are triploid, i.e., 
either A. tremblayi or A. platineum (Figure 2). 
The identity of ROM 4000 is an enigma. 
Because, for its length, it has a narrow snout 
(Figure 2), this specimen is atypical of any 
species in the complex. Uzzell (1964) examined 
two specimens from Findlay, Ohio (Figure 2) 
that were equally atypical. On the basis of the 
"numerous discrete light spots" on the venter, he 
concluded that these individuals closely re- 
semble A. tremblayi. ROM 4000, on the other 
hand, because it is gray-brown in color and lacKs 
any spotting, more closely resembles A. jef- 
fersonianum. It seems unjustified, therefore, to 
assign this specimen to .4. /rcm^/^v/solely onthe 
basis of the similarity in snout width with those 
from Findlay. Ohio. ROM 4000 morpho- 
logically resembles Ambystoma texanum, be- 
cause of its narrow snout width. It has, however, 
a greater snout-vent length and total length than 
A. texanum females (Smith 1961). The maxil- 
lary and premaxillary teeth are peg-shaped and 
do not hook inwards (cf, Tihen 1958, p. 7), and 
occur in a single row anteriorly. The one row of 
vomerine teeth is separated into three groups by 
breaks posterior to the internal nares, with the 
two lateral groups of these teeth extending 
beyond these nares. Although the tongue is 
partially decomposed, the lingual plicae ap- 



parently diverge from the posterior margin. 
With respect to these characters, ROM 4000 can 
be undoubtedly referred to the A. Jefferson- 
ianum complex, rather than to A. texanum (cf, 
Anderson 1967; Smith 1961, p. 24; Tihen 1958, 
p. 7). On a geographical basis, it is unreasonable 
to refer ROM 4000 to A. texanum since the latter 
species is known in Canada only from Pelee 
Island to extreme southwestern Ontario (Ander- 
son 1967). 

Discussion 

The distributional data presented here pro- 
vide evidence that the post-glacial dispersal of .4. 
tremblayi, A. platineum, and A. Jeffersonianum 
into southern Ontario has been more extensive 
than was previously documented. It is par- 
ticularly interesting to note that A. Jeffer- 
sonianum, a more southern species that is 
presumably more adapted to warmer climates 
(Uzzell 1964). occurs in Vermont and Ontario 
far north of the southern extent of the Wisconsin 
ice sheet. 

All four species of this complex occur in both 
glaciated and unglaciated areas of northeastern 
North America and breed in both permanent 
and temporary bodies of water. An evaluation of 
the habitat descriptions from the literature 
suggests that the diploid species, and their 



1978 



Weller et al.: Ambystoma jeffersonianum Complex, Ontario 



179 



Females Males 



1 A I 1 FT-n 

I, l-^l ^J 38 

% 1.1- 96 15 31 I 



c 0.9- 
I 0.7- 



18.0- 
16.0- 



101' 



i!c^' 14.0H 

u O 

2 - 12.0 

"b^e 10.0 
m |_ 

§ ^ 8.0 



6.0- 



7^ 
+ 



71 



I. 



32 



NY& 
Ohio 



Females Males 
I 1 I 1 



15 



43 



5 39 



n*+t 



— i""i 1 — I — I r— I — I I I 

Ont USA Wis Ont USA Ind Ont USA Ky Ont USA 

&NY 

A.tremblayi A. platineum A. jeffersonianum 

Figure 4. (A) Relation of tail length to snout-vent length, and (B) mean of individual salamander mean erythroctye area 
for adult salamanders of the A. jeffersonianum complex. Vertical lines show the range, horizontal lines the mean, and 
numbers the sample size. " signifies the inclusion of 50 males from Peel County reported by Weller and Sprules(1976); 
'' the inclusion of one specimen from Halton County reported by Menzel and Goellner (1976); and, 'the inclusion of 
four specimens from Peel County identified by W. F. Weller and B. W. Menzel (unpublished data). Specimens from 
Wisconsin, Indiana, New York, Ohio, and Kentucky are those reported by Menzel and Goellner (1976), and from 
USA, those reported by Uzzell (1964) from throughout the species' range. 



associated Iriploid species, occupy different 
habitats. Ambystoma laterale and A. tremblayi 
generally occur in woodlots near open field 
ponds (Anderson and Giacosie 1967), near 
boggy and marshy areas (Bishop 1941, 1943; 
Bleakney 1954; Cook 1967; Menzel and Goellner 
1976; Smith 1961; Wilbur 1972), near roadside 
ditches in sandy areas (Cook 1967; Gilhen 1974; 
Logier 1928), near backwaters of small lakes 
(Edgren 1949), and in poorly drained woodlots 
(Minton 1954, 1972; Smith 1961; Stille 1954). 
Ambystoma jeffersonianum and A. platinemn. 
on the other hand, occur in comparatively 
undisturbed, well-drained forested areas (An- 
derson and Giacosie 1967; Creusere 1971; 



Douglas 1974; Minton 1954, 1972; Wacasey 
1961). 

The habitats from which we collected sala- 
manders correspond with those reported in the 
literature. Ambystoma laterale and A. tremblayi 
were collected from flooded roadside ditches 
and grassy fields whereas A. jeffersonianum and 
A. platineum were collected from ponds in well- 
drained woodlots. 

At one locality in Ontario (Halton County, 
3.9 km south and 0.9 km east of Campbell- 
ville), we collected A. jeffersonianunu A. 
platineum, and one A. laterale male (NMC 
17563 (1)) from a roadside pond situated at the 
edge of a well-drained forested slope. Although 



180 



The Canadian Field-Naturalist 



Vol. 92 



A. laterale and A. tremblayi have been collected 
from nearby ponds and ditches, A. jeffer- 
sonianum and A. platineum were collected only 
from this pond. Although the electrophoretic 
patterns of blood plasma proteins of specimens 
collected do not suggest that A. laterale males 
successfully mate with A. jeffersonianum fe- 
males in this Halton County pond, such a 
phenomenon cannot be ruled out. The electro- 
phoretic pattern of one diploid individual taken 
with A. tremblayi from a pond in Waterloo 
County, Ontario, which resembles A. laterale in 
morphology, coloration and spotting, clearly 
shows two bands where one is expected (B. W. 
Menzel, personal communication). Although a 
final analysis has not been completed, it is 
conceivable that this individual is a diploid 
hybrid. 

The proportionally longer tails of Ontario A. 
platineum and A. jeffersonianum could be an 
adaptation for survival at these northern 
latitudes. That a potential, metabolic energy 
source (i.e., lipids) is stored in the tail has been 
reported for Batrachoseps attenuatus, a west- 
coast North American plethodontid salamander 
by Maiorana(1976). She found that to maximize 
survival, adult salamanders will often regenerate 
broken tails rather than enlarge ovarian follicles 
if there is insufficient energy to do both. 

Because of the difficulty in distinguishing 
members of this complex on the basis of 
morphology and pigmentation alone, we recom- 
mend that living, rather than preserved, speci- 
mens be submitted for identification. At least the 
ploidy of individuals can be determined on the 
basis of erythrocyte area (Uzzell 1964) or 
erythrocyte nuclear diameter (Wilbur 1976). The 
four species of this complex can be conclusively 
distinguished by the electrophoretic patterns of 
the blood plasma proteins (Uzzell and Goldblatt 
1967). 

Acknowledgments 

We thank F. R. Cook, National Museum of 
Natural Sciences, Ottawa; R. \. Crombie, Na- 
tional Museum of Natural History, Washington; 
and E. J. Crossman, Royal Ontario Museum, 
Toronto for allowing us to examine and report 
on the specimens in their respective institutions. 
We are grateful to Craig A. Campbell, Water- 
loo, Ontario for allowing us to cite his 



unpublished record of A. platineum from 
Waterloo County, and to Bruce W. Menzel, 
Iowa State University for permitting us to cite 
and comment upon his electrophoretic findings. 
We thank F. R. Cook and Thomas Uzzell for 
reading the manuscript and offering valuable 
suggestions for its improvement. 

Specimens Examined 

Numbers refer to museum catalogue numbers, and. in 
parentheses, number of specimens. 

A. laterale, preserved males: Brant Co., St. George, NMC 
15057(17); Carleton Co., Harwood Plains, NMC 2720(1), 
NMC 6887(4), NMC 6888(6), NMC 6937( 1). NMC 7685(8). 
NMC 769 1( 18), NMC 10926( 1 ); Carleton Co., Bells Corners, 
NMC 8350( 17), NMC 8354(5), NMC 8356( 1 ), NMC8357( 1 ), 
NMC 8363(13), NMC 9215(2); Russell Co., Cumberland, 
NMC 9234(5), NMC 10951(1). 

A. laterale, males examined alive: Halton Co., 3.7 km south 
and 0.9 km east of Campbellville. NMC 17563(1); Halton 
Co.. 4.0 km south and 1.0 km east of Campbellville, NMC 
17562(1); Halton Co., 4.1 km south of Campbellville, NMC 
17560(4), NMC 17561(3). 

A. tremblayi, preserved specimens (Figure 1, four western- 
most circles): Bruce Co., Lucknow, USNM 10830(1); Brant 
Co., St. George, NMC 15057(12); Halton Co.. 4.1 km south 
of Campbellville, NMC 17572(1); Lincoln Co., St. Cathar- 
ines, USNM 4690(1), USNM 4822(2), USNM 14471(2). 
(Figure 1, four easternmost circles): Carleton Co., Harwood 
Plains, NMC 2720(1), NMC 6937(2). NMC 7685(2). NMC 
7691(8), NMC 7831(3), NMC 10926(1); Carleton Co., Bells 
Corners, NMC 8357(2), NMC 8363(1); Carleton Co., 
Ottawa, NMC 2726(7); Russell Co., Cumberland, NMC 
9234(66), NMC 10951(55). Examined alive (Figure 1, solid 
circle east of Georgian Ba> ): Muskoka Dist., 17.7 km south 
of Dorset, NMC "l7575( I). E.xamined alive (Figure 3 A), 
south to north, hollow circles): Halton Co., 4.1 km south of 
Campbellville, NMC 17569(3), NMC 17570(7), NMC 
17571(4). NMC 17573(6); Halton Co.. 3.7 km south and 
0.9 km east of Campbellville, NMC 17574(9). 
A. platineum, preserved specimens (Figure 1. west to east, 
solid diamonds, excluding combination s\mbol): Waterloo 
Co., Waterloo region, NMC 13464(1), NMC 13465(1); York 
Co., "near Toronto," ROM 3714-17(4); Northumberland 
Co., Port Hope, ROM 122(1). Examined alive (Figure 3 A, 
south to north, solid circles): Wentworth Co., Mineral 
Springs, NMC 17585(28); Halton Co., 3.9 km south and 
0.9 km east of Campbelhille. NMC 17586(1). NMC 
17587(2), NMC 17588(3), NMC 17589(3). NMC 17590(1). 
NMC 17591(1), NMC 17592( 1 ), NMC 17593(3); Halton Co., 
2.1 km south and 1.3 km west of Speyside, NMC 17584(7); 
Halton Co., 1.6 km south and 1.2 km west of Speyside, 
NMC 17583(13); Peel Co., near Streetsville, NMC 
17576(10), NMC 17577(1), NMC 17578(2), NMC 17579( 15). 
NMC 17580(5), NMC 17581(4), NMC 17582(9). 
A. Jeffersonianum. females examined alive (Figure 3 A, south 
to north, solid circles): Wentworth Co., Mineral Springs, 
NMC 17594(1); Halton Co., 3.9 km south and 0.9 km east of 
Campbellville, NMC 17595(1), NMC 17596(1), NMC 
17597(1); Halton Co., 2.1 km south and 1.3 km west of 
Speyside. NMC 17598(2); Halton Co.. 1.6 km south and 



1978 



Weller et al.: Ambystoma jeffersonianum Complex, Ontario 



181 



1.2 km west of Speyside, NMC 17599(1); Peel Co., near 
Streetsville, NMC 17600(2), NMC 17601(1), NMC 17602(9). 
A. jeffersonianum, males examined alive (Figure 3B, south 
to north): Wentworth Co., Mineral Springs, NMC 17564(4); 
Halton Co., 3.9 km south and 0.9 km east of Campbellville, 
NMC 17565(1); HaltonCo., 1.6 kmsouthand 1.2 km west of 
Speyside, NMC 17566(1); Peel Co., near Streetsville, NMC 
15415(2), NMC 17458(1), NMC 17459(2). NMC 17567(1), 
NMC 17568(1). 

Unidentified females; Middlesex Co., London, ROM 
1472-74(3); York Co., vicinity of Toronto, ROM 54(1), 
ROM 55(1), ROM 1015(1), ROM 4000(1), ROM 5006(1); 
Victoria Co., Bobcaygeon, ROM 5754(1). 

Literature Cited 

Anderson, J. D. 1967. Ambystoma texanum. In Catalogue 
of American amphibians and reptiles, pp. 37.1-37.2. 

Anderson, J. D. and R. V. Giacosie. 1967. Ambystoma 
laterale in New Jersey. Herpetologica 23(2); 108-1 1 1. 

Bishop, S. C. 1941. The salamanders of New York. New 
York State Museum Bulletin 324; 1-365. 

Bishop, S. C. 1943. Handbook of salamanders — The 
salamanders of the United States, of Canada, and of 
Lower California. Comstock Publishing Company, 
Ithaca, New York. 555 pp. 

Bleakney, J. S. 1954. Range extensions of amphibians in 
eastern Canada. Canadian Field-Naturalist 68(4): 167- 
171. 

Cook, F. R. 1967. An analysis of the herpetofauna of 
Prince Edward Island. National Museum of Canada 
Bulletin Number 212, Biological Series Number 75. 
60 pp. 

Cope, E. D. 1889. The Batrachia of North America. 
Bulletin of the United States National Museum Number 
34: 1-525. 

Creusere, F. M. 1971. Range extension of the triploid 
Ambystoma platineum. Journal of Herpetology 5(1-2): 
63-64. 

Douglas, M. E. 1974. A study of three sympatric ambysto- 
matid salamanders in Bernheim Forest, Bullitt County, 
Kentucky. M.Sc. thesis. University of Louisville, Ken- 
tucky. 207 pp. 

Edgren, R. A. 1949. An autumnal concentration of /l/?;^- 
stoma jeffersonianum. Herpetologica 5(6): 137-138. 

Gilhen, J. 1974. Distribution, natural history and mor- 
phology of the blue-spotted salamanders, Ambystoma 
laterale and A. tremblayi in Nova Scotia. Nova Scotia 
Museum, Curatorial Report Number 22: 1-38. 

Logier, E. B. S. 1928. The amphibians and reptiles of the 
Lake Nipigon region. Transactions of the Royal Canadian 
Institute 14(2): 279-291. 

Maiorana, V. C. 1976. Size and environmental predicta- 
bility for salamanders. Evolution 30(3): 599-613. 



Menzel, B. W.and K. E.Goellner. 1976. Occurrence of the 

Blue-spotted salamander, Ambystoma laterale, in Iowa. 

Proceedings of the Iowa Academy of Science 82(3-4): 
182-186. 
Minton, S. A., Jr. 1954. Salamanders of the Ambystoma 

jeffersonianum complex in Indiana. Herpetologica 10(3): 
173-179. 
Minton, S. A., Jr. 1972. Amphibians and reptiles of 

Indiana. Indiana Academy of Science, Indianapolis, 

Indiana. 346 pp. 
Smith, P. W. 1961. The amphibians and reptiles of Illinois. 

Illinois Natural History Survey Bulletin 28(1): 1-298. 
Stille, W. T. 1954. Eggs of the salamander Ambystoma 

jeffersonianum in the Chicago area. Copeia 1954(4): 300. 
Tihen, J. A. 1958. Comments on the osteology and phylo- 

geny of Ambystomatid salamanders. Bulletin of the 

Florida State Museum, Biological Sciences 3(1): 1-50. 
Uzzell, T. 1964. Relations of the diploid and triploid species 

of the Ambystoma jeffersonianum complex (Amphibia, 

Caudata). Copeia 1964(2): 257-300. 
Uzzell, T. 1967a. Ambystoma jeffersonianum. In Cata- 
logue of American amphibians and reptiles, pp. 47.1- 

47.2. 
Uzzell, T. 1967b. .Ambystoma laterale. In Catalogue of 

American amphibians and reptiles, pp. 48.1-48.2. 
Uzzell, T. 1967c. Ambystoma platineum. In Catalogue of 

American amphibians and reptiles, pp. 49.1-49.2. 
Uzzell, T. 1967d. Ambystoma tremblayi. In Catalogue of 

American amphibians and reptiles, pp. 50.1-50.2. 
Uzzell, T. and S. A. Goldblatt. 1967. Serum proteins of 

salamanders of the Ambystoma jeffersonianum complex, 

and the origin of the triploid species of this group. 

Evolution 21(2): 345-354. 
Wacasey, J. W. 1961. An ecological study of two sympatric 

species of salamanders, Ambystoma maculatum and 

Ambystoma jeffersonianum in southern Michigan. Ph.D. 

thesis, Michigan State University. 117 pp. 
Weller, W. F. and W. G. Sprules. 1976. Taxonomic status 

of male salamanders of the Ambystoma jeffersonianum 

complex from an Ontario population, with the first 

record of the Jefferson salamander, A. jeffersonianum 

(Green), from Canada. Canadian Journal of Zoology 

54(8): 1270-1276. 
Wilbur, H. M. 1972. Competition, predation, and the 

structure of the Ambystoma- Rana svlvatica community. 

Ecology 53(1): 3-21. 
Wilbur, H. M. 1976. A sequential sampling procedure for 

identifying triploid salamanders. Copeia 1976(2): 391- 

393. 



Received II July 1977 
Accepted 2 December 1977 



Distribution of Giant Cow Parsnip {Heracleum 
mantegazzianum) in Canada 



J. K. Morton 

Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 

Morton, J. K. 1978. Distribution of Giant Cow Parsnip (Heracleum mantegazzianum) in Canada. Canadian Field- 
Naturalist 92(2): 182-185. 

The Giant Cow Parsnip, Heracleum mantegazzianum, occurs in many stations in southern Ontario and also in the Vancouver 
area. Its known distribution in southern Ontario is mapped. A native of the Caucasus and southwestern Asia, it was probably 
introduced into Canada from Europe as a garden plant and has escaped to become a potentially serious weed. Methods of 
control are possible by using existing knowledge of its life cycle and general biology. Characters that distinguish it from the 
similar H. maximum and H. sphondylium are its large size, the elliptic fruits and their broad oil canals. The plant is a cause of 
severe and painful blistering and dermatitis as a result of a phototoxic reaction of the sap when in contact with the skin. 

Key Words: Heracleum, weeds, dermatitis, phototoxic, herbicides. 



The Giant Cow Parsnip or Giant Hogweed 
{Heracleum mantegazzianum Sommier and 
Levier) is an umbelliferous plant which attains a 
height twice that of a man, with umbels reaching 
several feet across. I reported its occurrence in 
Canada in 1975 on the basis of plants found the 
previous year growing in and around Tara in the 
Sauble Valley of Bruce County in southern 
Ontario (Morton 1975). This record elicited a 
number of letters from naturalists who reported 
the presence of the species in other localities in 
Ontario. In particular, George Thomson drew 
my attention to a note on the occurrence of the 
species in the Keppel area (Owen Sound) which 
he put in the newsletter for January/ February 
1971 of the Michigan Botanical Club (South- 
eastern Chapter). These records, together with 
those resulting from a search for the species 
which I have made over the last two summers, 
indicate that it has attained a wide distribution 
in southern Ontario and may be spreading 
rapidly. It is also established on the other side of 
our continent, in Seattle, and has recently been 
reported from Vancouver (Kamermans 1977). 
The species is native in the mountains of the 
Caucasus and southwestern Asia but it was 
introduced into European gardens before the 
turn of the century for its impressive appear- 
ance. It soon escaped from cultivation and is 
now widely naturalized across Europe and in 
Britain. It was presumably introduced into 
Canada for similar reasons, for it is a most 
spectacular plant particularly when in flower in 
late June and July. Its introduction probably 
dates back many years, for George Thomson 



informs me that he recalls seeing the plant on the 
Bruce Peninsula in the late 1940s or early 1950s 
and C. L. Hitchcock (personal communication) 
has known of its occurrence in Seattle for 25 
years. 

The Giant Cow Parsnip usually grows in deep 
rich moist soils in semi-shade and is most 
frequently found along rivers and streams or 
planted in gardens. The center of its present 
distribution in Canada is the Bruce Peninsula 
southwards to Perth County and Waterloo 
Region, but it has spread as far east as 
Haliburton County and north to at least the tip 
of the Bruce Peninsula at Tobermory and 
possibly (unconfirmed report) Manitoulin Is- 
land. Figure 1 indicates the distribution of H. 
mantegazzianum in Ontario as known to me at 
the time of writing. Readers are asked to watch 
for the Giant Cow Parsnip on their travels. I 
shall be very interested to hear of further records 
for the species. 

Though enormous size is its most ready means 
of identification, H. mantegazzianum may be 
confused with large specimens of our native Cow 
Parsnip (also known as Hogweed and Master- 
wort), H. maximum Bartr. (= H. lanatum 
Michx.). The fruit, however, is diagnostic in size 
and shape and in the width of the oil or resin 
canals (vittae) (see the accompanying photo- 
graph. Figure 2). Another useful character is the 
dark reddish-purple stem, and the spotting of the 
leaf-stalks and young stems with a similar 
color, each spot having a pustulate bristle. These 
bristles stick into the skin and break off to cause 
irritation. The stems and leaf-stalks of H. 



182 



1978 



MORTON: Giant Cow Parsnip in Canada 



183 




Figure i. Distribution of the Giant Cow Parsnip in southern Ontario. 




/r 



1 1 \) 





\ ^■^ » 



KETPiC 



'MMIl!!!!!!!!! 
I 3 



4 



MHini 



( I 



! 1 1 



7 



Figure 2. Fruits of species of Giant Cow Parsnip found in eastern Canada. Left pair, H. mantegazzianum; center pair, 
H. maximum; right pair, H. sphondylium. 



184 



The Canadian Field-Naturalist 



Vol. 92 



maximum lack the spotting and the pustulate 
bristles though they often have scattered soft 
hairs. We have another species of Cow Parsnip 
in Ontario, H. sphondylium L. which is a rare 
alien weed introduced from Europe. It is usually 
smaller than either of the other species and has 
fruits similar to those of H. maximum. Its stems, 
leaves, and leaf-stalks have long, white, coarse 
hairs. 

Though H. mantegazzianum is a very hand- 
some, spectacular and even beautiful plant, it 
has the potential to become a serious weed, for in 
addition to having the irritating bristles which 
break off in one's skin, it exudes a clear watery 
sap which can cause severe blistering and a very 
painful dermatitis. I experienced the effects of 
the sap in July 1976 after collecting herbarium 
material of the plant at the height of its flowering 
season. The cut stems and leaf-stalks exude 
copious amounts of sap at this stage in the 
plant's development and a drop of this fell on the 
side of my leg. It was quickly removed but the 
next day a large and painful watery blister 
developed. It took two weeks for this to begin to 
heal and a red scar remained for several months. 
The hazards of contact with this plant attracted 
press comment in Britain in 1970 after many 
cases of blistering were reported from various 
parts of the country. A comment in the Lancet 
(4 July 1970) was that reaction to the sap is 
stimulated by exposure to the sun and that a 
permanent brown pigmentation of the skin often 
ensues. In the same year reports appeared in the 
Wiarton Echo (2 July and 17 September) of a 
child contracting blisters and being hospitalized 
after playing with the large bamboo-like stems of 
this plant from the Southhampton area of 
Ontario. 

It is clear that the rapid spread of the Giant 
Cow Parsnip presents a potential hazard and if it 
continues control measures will, unfortunately, 
be necessary. I would caution anyone coming 
across the plant to avoid contact with the juices 
from the broken stems and leaves. The hazards 
are apparently greatest at the height of the 
growing season (June and July) when sap exudes 
freely from broken plants, and on hot sunny 
days when perspiration and sunlight accentuate 
the effect of the sap. Juices on the skin should be 
washed off immediately with copious amounts 
of water, or better still, soap and water, and a 



skin lotion of the sort used to relieve irritation 
and insect bites applied. Corticosteroid lotions 
or gels (not creams) may be the most effective 
method of treatment. Medical advice should be 
sought if there are signs of reaction. 

The underground tuberous rootstock, rapid 
growth, and abundant seed-production of this 
plant make control or eradication difficult. The 
Giant Cow Parsnip is a perennial but it takes 
several years (four in plants grown experi- 
mentally at Waterloo) from germination of the 
seed to the production of the flowering shoot. It 
is probable that the plant is often monocarpic 
and dies after flowering and fruiting. This 
occurred with plants that I grew in cultivation, 
but examination of ones growing elsewhere 
suggests that the rootstocks may on occasion 
produce additional crowns after flowering, and 
these continue to grow. Though most of the 
herbicides in common use for the control of 
broad-leaved plants (e.g., 2,4-D, TBA, MCPA 
and dicamba) will kill the above-ground parts of 
the Giant Cow Parsnip they do not completely 
eradicate the persistent rootstocks. Successful 
eradication of the plants has been obtained by 
the use of 2,4-D acid in oil emulsion, and with a 
TBA and MCPA mixture (Drever and Hunter 
1970). Spraying should be carried out early in 
the season when the leaves are green and actively 
growing, i.e., before flowering, and the plants 
should be thoroughly sprayed to ensure com- 
plete coverage. Control can be achieved also by 
cutting the plants down each year early in the 
growing season, but the rootstocks remain alive 
for many years when prevented from flowering 
and seeds in the soil will continue to germinate. 
In Europe effective control has been obtained by 
allowing cattle to graze in the area where the 
plants are growing. Apparently the trampling of 
the cattle not only knocks down the leaves and 
stems but also crushes the crowns of the 
rootstocks and this usually prevents further 
growth. 

The fruits are large and split into two winged 
propagules each containing a seed. These are 
carried short distances by the wind. The 
principal natural mode of dispersal, however, 
appears to be by water, and flotation tests 
indicate that the fruits float in water for up to 3 
days (Clegg and Grace 1974). The Giant Cow 
Parsnip frequently grows on river banks, hence 



1978 



MORTON: Giant Cow Parsnip in Canada 



185 



in times of flood, dispersal over distances of 
many kilometres can be expected. Human 
activities are doubtless an equally effective 
means of dispersal as fruits are introduced 
intentionally or accidentally. Inflorescences are 
often collected for decoration and seeds are 
sown in gardens. The seeds retain their viability 
for several years. Those that I have kept dry at 
room temperature were still viable after 7 yr. 
Hence even if the plant is eradicated from a 
locality it is liable to reappear, as seed lying 
dormant in the ground germinates. In view of the 
potential hazards of this plant, should it spread 
extensively in this country, further studies on its 
life history and on methods of control are clearly 
desirable. 



Literature Cited 

Clegg, L. M. and J. Grace. 1974. The distribution of 
Heracleum mantegazzianum Somm. & Levier near Edin- 
burgh. Transactions of the Botanical Society of Edin- 
burgh 42: 223-229. 

Drever, J. C. and J. A. A. Hunter. 1970. Giant Hogweed 
dermatitis. Scottish Medical Journal 15: 315-319. 

Kamermans, J. K. 1977. A hairy horror in my Huron 
haunts. Wood Duck 31: 49-50. 

Morton, J. K. 1975. The Giant Cow Parsnip, Heracleum 
mantegazzianum Umbelliferae, in Canada. Canadian 
Field-Naturalist 89: 183-184. 



Received 11 October 1977 
Accepted 3 February 1978 



Notes 

Morphology, Diet, and Parasitism in Quebec Black Bears 

Ian Juniper 

Wildlife Research Service, Department of Tourism, Fish and Game, 9530, rue de la Faune, Orsainville, Quebec GIG 5E5 
Service de la Recherche Faunique, Ministere du Tourisme, de la Chasse et de la Peche, c.p. 7200, Charlesbourg, Quebec 
GIG 5E5 

Juniper, Ian. 1978. Morphology, diet, and parasitism in Quebec Black Bears. Canadian Field-Naturalist 92(2): 186-189. 

Data on age classes, morphology, diet, and incidence of endoparasitism were obtained from 30 Black Bear ( Ursus americanus) 
killed north of Montreal during spring and summer 1972. Male bears averaged younger than females (4.0 versus 6.7 years) and 
were larger by age class. The heaviest animal examined was a male of unknown age weighing 154.0 kg. The heaviest female 
recorded was 5 years old and weighed 121.5 kg. Vegetation was shown to be of primary importance in the diet of bears 
examined, while animal remains including fish and a trace of insects were of secondary importance. The incidence of 
endoparasitism was low, with four specimens infected by Ascaris, two with Coccidia, and one with Diphyllobothrium. No 
evidence of Trichinae was discovered. 
Key Words: Quebec, Black Bear, morphology, diet, parasitism. 



There are few data on the physical characteristics 
and seasonal diet of the Black Bear ( Ursus ameri- 
canus) in the Province of Quebec. The incidence of 
endoparasitism in Quebec bears is somewhat better 
known (Frechette and Panisset 1973), but this aspect 
of Black Bear biology remains incompletely de- 
scribed. The present project was designed to provide 
information on all of the above. 

Study Area 

Bears for the study were collected in two areas north 
of Montreal (Figure 1). The first area begins some 
40 km north of Mont Laurier and covers about 
650 km^ of public land, 1 14 km^ of which is leased by 
the Quebec government to a licensed outfitter, J. B. 
Scott Incorporated, the remainder being leased to 
private hunting and fishing clubs. The topography is 
low and rolling. The forest type is basically boreal. 

The second area is located about 105 km north of 
Montreal in the south-central section of Mont 
Tremblant Provincial Park and covers about 
1000 km-. Rowe (1972) places this area within the 
Laurentian section of the Great Lakes - Saint 
Lawrence Forest region. It is a zone of transition to 
the boreal forest and is characterized by upland 
tolerant hardwoods with mixed woods and softwood 
found in the valleys. The topography is dissected and 
rugged, in both areas lakes and streams are common. 

Materials and Methods 

Data were obtained from freshly killed bears 
through the cooperation of a number of sport hunters 
during the spring of 1972. Also, a number of bears 
which became troublesome for campers in the park 
were judged undesireable and were destroyed by 





75" 15' W 


74°30'W 








1 

• 


1 








• 






47" 
15' 
N 




^ Menjou Depot 

1 


Ij PARC PROVINCIAlX 


47' 

15' 
N 


46° 

30' 
N 


- 


4- — -N 

Mont- Loune\,.^^____^.^ 


/MONT TREMBLANtX 


46- 
30 

N 






, L Annonciation^B 






J ^ 


\V^ 






\ 


1 


^\y• . .-. 




^oint-Jovite '° 






75" I5'W 


74" 30' W 



• Figure 1 — Map showing distribution of bear kill in the 
study area. 

Department personnel. Advantage was taken of this 
situation to gather additional information. 

Animals killed by hunters were examined at the 
hunting camp of J. B. Scott. Bears taken within the 
park boundaries were autopsied nearby at the Wildlife 
Management Service station at Sainte Faustin. The 



186 



1978 



Notes 



187 



date and location of each kill was recorded, the sex 
was determined, and weights, rounded to the nearest 
0.5 kg, were obtained by means of platform scales. 
Total zoological lengths of the animals were measured 
to the nearest 5 mm with a steel-roll tape. When 
possible, the second or third premolar was extracted 
for age determination. The tooth was decalcified, 
sectioned, and stained to reveal the cementum layers 
(Stoneberg and Jonkel 1966). 

Autopsies were performed as soon as possible after 
a kill. Stomach contents of bears were examined 
macroscopically and divided into four categories: 
plant, mammals/ fishes, insect, and undetermined. 
Gross volumetric estimates for each category were 
made visually. A section of the diaphragm near the rib 
cage was removed and kept frozen until examined for 
Trichinae larvae. The intestines were removed, tied 
off, and preserved in a solution of 5% formalin and 
later examined for the presence of gastrointestinal 
parasites. 

Results 

Between 21 May and 26 August 1972, 30 bears were 
examined. Twenty-one of these were hunter-killed. 
The remaining nine were collected during the summer 
bear control program in Mont Tremblant Park. Table 
1 records the ages, sex, weights, and total lengths. 

Ages were determined for 23 bears. The youngest 



was a male yearling and the oldest a 12-year-old 
female. For seven bears the ages were not determined, 
but their weights and measurements were used to 
estimate their maturity. Six of the seven were 
considered to have been adults. The seventh, a male, 
was probably a yearling. No young-of-the-year were 
included in the sample. Males averaged younger than 
females for both regions. The mean age for males was 
4.0 years (n = 16) and 6.7 years for females (n - 7). 
Bears from the park averaged 5.5 years as compared 
to 4.6 for the outfitter's sample. 

The sex-ratio favored males (200: 100). Sport 
hunters killed twice as many males as females (14: 7). 
Six males and three females were taken from the park. 

The weights of 30 bears were recorded. The heaviest 
animal was an unaged male weighing 154.0 kg. Bears 
of age class 5 averaged heaviest for both sexes. The 
data also showed that males of each class were heavier 
than females of the same age class. 

The total lengths for 27 bears ranged from 1 145 mm 
for a male yearling to 1 830 mm for a male of age class 
5. The longest female measured 1640 mm and was of 
age class 5. 

Diet 

The stomach contents of 30 bears were examined 
(Table 2). The stomachs of two specimens were empty, 
but the intestines of these animals contained food 



Table 1 — Mean weights and mean total lengths by sex and age of 30 Black Bears taken north of Montreal, Quebec, 
21 May -26 August 1972 



Sector 



Sex 



Age class 



Number 



Weight 
(kg) 



Total length 
(mm) 



Outfitter 



Park 



m 


1 


1 


m 


2 


2 


m 


3 


4 


m 


4 


2 


m 


5 




m 


7 




m 


9 




m 


adult 


2 




4 






5 


2 




6 






12 






adult 


2 


m 


2 




m 


4 




m 


5 




m 


7 




m 


yearling 




m 


adult 




f 


4 




f 


11 




.f 


adult 





35.0 


1145 


50.5 


1285 


38.0 


1310 


59.5 


1505 


113.5 


1830 


53.0 


1500 


81.5 


1625 


81.5 


1645 


43.5 


1170 


91.0 


1530 


55.5 


1370 


59.5 


1600 


49.0 


1405 


27.0 


980 


65.5 


1450 


104.5 


1625 


84.0 


1560 


28.0 


NA 


154.0 


1725 


58.0 


NA 


58.5 


1485 


49.5 


NA 



The Canadian Field-Naturalist 



Vol. 92 



material. Of the remaining 28 stomachs, 24 each 
contained a predominance of green vegetation, and 
three each contained mostly animal remains. The 
stomach of one bear contained garbage only. No 
evidence of moose (Alces alces) hair was found in any 
of the stomachs or intestines examined during the 
study. The animal remains were identified as fish, 
meat from garbage dumps, and bait set out by 
hunters. Most fish remains were identified as dore 
{Stizostedion vitreum) and sucker {Catastomus sp.). 

Table 2 — Diet of 29 Black Bears from the area north of 
Montreal, 21 May to 26 August 1972 



Food 












category 


Frequency 


% 


occurrence 


% 


volume 


Plants 


26 




86.6 




70.9 


Mammals/ 












fishes 


21 




70.0 




24.6 


Insects 


1 




tr. 




tr. 


Undetermined 


5 




1.7 




4.3 



Endoparasitism 

The intestinal tract of each bear was examined for 
parasites (Table 3). The adult form of the nematode 
Ascaris sp. was found in two specimens, and eggs of 
the same species were isolated from two others. Two 
specimens contained the protozoon Coccidias^p. and 
the eggs of hookworm. Diphyllobothrium ursi was 
isolated from one other intestinal tract. No evidence 
of intestinal parasitism was reported from the 
remaining 23 bears. No evidence of Trichinae spp. 
larvae was found. 



Table 3 — The incidence of endoparasites in 30 Black Bears 
taken north of Montreal, Quebec, between 21 May and 26 
August 1972 



Parasite 



Frequency % occurence 



Ascaris (adult or egg) 


4 


13.3 


Hookworm (egg, sp. ?) 


2 


6.7 


Diphyllobothrium ursi (adult) 


1 


3.3 


Coccidia (adult) 


2 


6.7 


Trichinae 





0.0 



Discussion 

There was a preponderance of males and a lack of 
cubs in the hunter-killed portion of the sample, 
primarily because the outfitter discourages the killing 
of cubs and females with cubs. Bears taken from the 
park did not include young-of-the-year as females 
with cubs appeared to avoid the major camping areas. 



But a cub sex-ratio favoring males has been reported 
from other areas (Spencer and Howard 1966; Jonkel 
and Cowan 1971). Willey (1970) reported an average 
sex-ratio of 124 M: 100 F for bears taken by hunters 
in Vermont, 1963-1968. 

The weights of Black Bears may vary appreciably 
during the year (Marks and Erickson 1966). Peterson 
( 1 966) mentions marked loss of weight in bear during 
early spring. Comparison of the weights of adult bears 
in this study with data from other regions (Peterson 
1966; Marks and Erickson 1966; Anonymous 1968) 
suggests that the bears from the Quebec study area 
were lighter. Because most of the animals in the 
sample were taken in the spring and early summer, 
however, the weights obtained may represent mini- 
mums for the year. The total lengths of the bears 
examined compare favorably with those provided by 
Peterson (1966). 

The Black Bear is protected from hunting within 
Mont Tremblant Park; therefore the higher average 
age for animals taken within the park as compared to 
that of hunter-killed bears is to be expected. The 
protection afforded maternal females by the out- 
fitter's clients undoubtedly contributed to the higher 
average age for females as compared to males taken in 
this sector. 

Most animals examined during the study were 
killed in late May or early June, a time coinciding with 
the peak calving period for moose in Quebec. Both 
sectors of the study area support substantial moose 
populations (Goudreault 1973, unpublished report, 
Wildlife Management Service, Saint-Faustin, Que- 
bec). No moose hair in any of the alimentary tracts 
examined suggests that the Black Bear is not a major 
cause of newborn moose mortality within the study 
area. 

The importance of green vegetation in the diet of 
the Black Bear has been reported for other regions 
(Tisch 1961; Hatler 1972). Spencer (1966), however, 
reported a high volume of animal food in the spring 
diet for bears in Maine. Both species offish identified 
in the stomach contents of bears from the present 
study are spring spawners and usually congregate in 
rivers and streams during this period. A number of 
these fish were probably taken directly off the 
spawning beds. 

The incidence of endoparasites found in the sample 
was not high. It is possible that the level of infestation 
rises as the summer progresses, but this is uncertain. 
Bears from this area may never be heavily parasitized. 
Sixty bears taken by hunters in Vermont in 1969 were 
examined for the presence of Trichinae (Willey 1970); 
only one was found to be infected. Jonkel and Cowan 
(1971) concluded that parasites and disease were not 
important in the Black Bears of Montana. 



1978 



Notes 



189 



Acknowledgments 

I thank L. Pilon and M. Goudreault of the Quebec 
Department of Tourism, Fish and Game for their 
assistance in various segments of the project. 1 also 
thank Jean-Louis Frechette of le College des 
Medecins Veterinaires, St-Hyacinthe, for his help in 
the parasitology work and A. Liebart of le Departe- 
ment d'Art Dentaire, Universite de Montreal for 
determining the age of bears by counting annuli in the 
teeth. Special thanks to D. Heyland, then of the 
Quebec Department of Tourism, Fish and Game, and 
to C. J. Jonkel of the University of Montana for their 
constructive criticism of the manuscript. 

Literature Cited 

Anonymous. 1968. The black bear. In Hinterland Who's 
who. Canadian Wildlife Service R 69-4/8. Information 
Canada, Ottawa. 6 pp. 

Frechette, Jean-Louis and Maurice Panisset. 1973. Con- 
tribution a Tetude de Fepizootiologie de la trichinose au 
Quebec. Canadian Journal of Public Health 64(Oct.): 
443^44. 

Hatler, David F. 1972. Food habits of black bears in 
interior Alaska. Canadian Field-Naturalist 86(1): 17-31. 



Jonkel, C. J. and L McT. Cowan. 1971. The black bear in 
the spruce-fir forest. Wildlife Monograph 27. 57 pp. 

Marks, S. A. and A. W. Erickson. 1966. Age determina- 
tion in the black bear. Journal of Wildlife Management 
30(2): 389-392. 

Peterson, R. L. 1966. Mammals of eastern Canada. Oxford 
University Press, Toronto. 465 pp. 

Rowe, J. S. 1972. Forest regions of Canada. Forestry 
Service Publication 1300, Information Canada, Ottawa. 
172 pp. 

Spencer, H. E., Jr. and E. Howard. 1966. The black bear 
and its status in Maine. Department of Inland Fisheries 
and Game, Game Division 4, Augusta, Maine. 55 pp. 

Stoneberg, R. P. and C. J. Jonkel. 1966. Age determina- 
tion of black bears by cementum layers. Journal of Wild- 
life Management 30(2): 411-414. 

Tisch, E. L. 1961. Seasonal food habits of the black bear in 
the Whitefish Range of Northeastern Montana. M.Sc. 
thesis. University of Montana. Ix + 108 pp. 

Willey, Charles H. 1970. The bear season. In Vermont 
Game Annual, 1970. Edited by Benjamin W. Day, Jr. 
Vermont Fish and Game Department, Bulletin 70-1. 
38 pp. 

Received 27 June 1977 
Accepted 29 December 1977 



Late Winter Bedding Practices of Moose in Mixed Upland Cutovers^ 

John G. McNicol- and Frederick F. Gilbert^ 

'Paper presented at the 13th annual North American Moose Conference and Workshop (1977) 
^Ontario Ministry of Natural Resources, Thunder Bay, Ontario P7E 6E3 
^University of Guelph, Guelph, Ontario NIG 2W1 

McNicol, John G. and Frederick F. Gilbert. 1978. Late winter bedding practices of moose in mixed upland cutovers. 
Canadian Field-Naturalist 92(2): 189-192. 

Moose (Alces alces andersoni) bedding sites within five northern Ontario mixed upland cutovers were examined during 
January and February to learn more about criteria affecting the choice of bed sites. Significant (P < 0.05) differences in snow 
depths in the vicinity of bedding sites, the proximity of potential windbreaking coniferous cover, and meteorological records 
concerning prevailing winds during the study period indicated that moose were utilizing immature coniferous tree species as 
windscreens and perhaps found snow conditions in the lee of these windbreaks preferable for bedding. Coniferous cover was 
usually least prevalent in southerly directions at bedding sites indicating that moose chose sites for bedding that minimized 
windchill and maximized exposure to solar radiation. 

Key Words: Moose (Alces alces andersoni), winter bedding, upland cutovers. 



There has been little investigation into moose 
bedding sites since the work done by Des Meules 
(1965). Because adult moose may bed up to seven 
times a day (Franzmann et al. 1976) and the lack of 
suitable bedding sites may temporarily be a limiting 
factor in the utilization of winter range (Des Meules 
1 964), the collection of further data on moose bedding 
practices became a secondary objective of moose 
habitat investigations (McNicol 1976). 



Study Area and Methods 

Data were collected on five 10- to 15-year-old mixed 
upland cutovers located on or close to the Mott Lake 
Road, a private secondary timber haul road appro.xi- 
mately 64 km northeast of Thunder Bay, Ontario. 

Soils in the study area are thin basal tills often 
averaging only a few centimetres to 0.3 m in depth. 
Bedrock exposures are frequent, as are swamps or 
poorly drained areas. The topography of the area is 



190 



The Canadian Field-Naturalist 



Vol. 92 



depth and depth of bed beneath the snow's surface, 
direction of the most (and least) potentially effective 
windbreaking cover, the species composition of the 
cover and diameter at breast height, and snow depth 
3.1 m from the bed site in the direction of the most as 
well as the least potentially effective windbreaking 
cover. "Cover" was arbitrarily defined as coniferous 
species that would provide a barrier to the wind. 

On occasions when a snowfall had occurred after a 
moose bed was made, the depth of fresh snow in the 
bottom of the bed was deducted from the depth of bed 
measurement and all snow depth measurements. 
Where a moose bed was located in uneven snowcover, 
the depth of bed and snow depth at bed site 
measurements were an average of the greatest and 
least snow depth associated with the moose bed. 

Results and Discussion 

Snow depths on the study cutovers during 1975 
reached 61.0 cm by 21 January and remained at that 
approximate depth until the end of February. On 10 
January, a 2.5-cm rainfall resulted in a substantial 
crust at the 46.0-cm level of the snow cover. The crust 
was composed of 0.6 cm of ice lying between two 1.9- 
cm layers of less dense ice crystals. 

Complete sets of data were collected on 48 of the 73 
moose beds encountered. Approximately 8 1 .0% of the 
moose bed sites were associated with immature 
coniferous clumps averaging from 2.5 to 7.6 cm in 
diameter at breast height (Table 1) when the mean 
snow depth at bedding sites was 67.3 cm (Table 2). 
Des Meules (1965) found that when snow depths 
ranged from 61 to 76 cm, 64.0% of the moose beds 
were found in association with immature coniferous 
clumps of less than 10.2 cm in diameter at breast 
height. He also noted that with snow depths of 
approximately 66 cm at bed sites, the mean distance 
from the center of the bed to the nearest "large" 
coniferous stem was 1.5 m. In this study, with 
identical snow depths, the most effective potential 

Table 2— Snow gradients in the vicinity of 48 moose beds recorded 13 January - 28 February 1975 on the 
Spruce River Road cutovers 



characterized by low gently rolling hills and by rocky 
ridge systems oriented in a northeast-to-southwest 
direction. 

The study area was situated in the boreal forest 
biome. The coniferous species distribution in the area 
of study was black spruce {Picea mariana), 51.0%; 
white spruce {Picea glauca), 10.0%; balsam fir {Abies 
balsamea), 13.0%; and jack pine {Pinus banksiana), 
26.0%. White birch {Betula papyrifera) and trembling 
aspen {Populus tremuJoides) represented 12.0 and 
13.0% respectively, of the total inventory of all 
species. 

The mean annual precipitation is approximately 
760 mm and during the winter season up to 203 cm 
of snow may fall, but average snow depths are 
approximately 76.0 cm. 

Data were collected at each moose bed location 
encountered while we were following moose tracks 
(1-3 days old) on mixed upland cutovers during 
January and February 1975. These included snow 

Table 1 — Tree species used for cover at bedding sites and 
their diameter at breast height in the Spruce River Road 
cutovers, 13 January - 28 February 1975 





Frequency of 


Diameter at 




occurrence 


breast 




at bed sites. 


height range. 


Species 


% 


cm 


Balsam fir 


52.0 


2.5- 7.6 


Balsam fir + 






black spruce 


15.1 


2.5- 10.2 


Black spruce 


6.8 


7.6- 10.2 


Jack pine 


23.3 


2.5- 7.6 


Black spruce + 






jack pine 


1.4 


2.5- 5.1 


White spruce 


— 


— 


Cedar 


1.4 


10.2-30.5 


Total 


lOO.O 





Date 
(1975) 



Mean depth of snow Mean depth at Mean depth of snow Difference in mean 

No. beds 3.1 m in direction bed site, in 3.1 m in direction snow depths over 6.2 m 

in sample of least cover, in cm of best cover, in in vicinity of bed, in 

cm cm cm 



13 Jan. 

25 Jan. 

31 Jan. 

4. 5 Feb. 

12 Feb. 

28 Feb. 
Total 
Means 



1 
7 
3 

16 

18 

3 

48 



61.0 
76.4 
77.0 
68.6 
76.4 
73.7 

72.2 



63.5 
64.0 
66.3 
68.1 
72.6 
69.3 

67.3 



52.3 
65.0 
62.2 
48.0 
64.3 
70.1 

60.3 



8.6 
11.4 
14.7 
20.6 
12.2 

3.6 



1978 



Notes 



191 



Table 3 — Mean distances to the most effective wind- 
breaking coniferous cover from the edge of moose beds in 
the Spruce River Road cutovers, 13 January - 28 February 
1975 





No. beds 


Average 


distance to the 


Date 


sampled 


most 


effective cover, in m 


13 Jan. 


7 






2.5 


20 Jan. 


11 






0.8 


25 Jan. 


7 






1.2 


31 Jan. 


11 






1.6 


4, 5 Feb. 


13 






1.4 


12 Feb. 


18 






1.0 


28 Feb. 


3 






2.1 


Total 


70 








Mean 








1.5 



windbreaking immature coniferous cover was an 
average of 1.5 m away from the edge of beds (Table 3). 

No direct data were collected to determine whether 
immature coniferous clumps were being used by 
moose as windscreens. In about 60% of the cases, 
however, the most effective cover was found either N, 
NE, NW, or W of the moose bed sites (Table 4). 
Weather records from the meteorological office in 
Thunder Bay reveal that prevailing winds were from 
these same directions approximately 63% of the 
days from 13 January to 28 February 1975, the period 
when bedding data were collected. 

Table 2 data illustrate the usual relationship 
involving potential windbreaking cover, depth of 
snow at bed site, and depth of snow 3.1 m in the 



direction of the most effective coniferous cover for the 
moose beds in this study. Moen (1973) studied the 
movement of air in the lee of a windbreak, and his 
findings suggest that turbulence develops in the lee of 
a windbreak. One main result is that air movement, 
instead of being directed horizontally, is directed 
downwards, sometimes perpendicular to the ground. 
Snowflakes following this pattern of air movement 
would tend to build up much more quickly in the area 
of the bed site and behind it than immediately adjacent 
to the windbreak where air movement is calm. It 
would seem likely that the significant (P<0.05, 
Duncan's multiple range test) snow-depth differences 
in the area of the conifer cover where moose bedded 
was created in a similar manner. For this to occur, the 
prevailing winds would have to be from the conifer 
cover towards the bed site, indicating that moose were 
bedding in the lee of conifer cover for protection from 
prevailing winds. Since there is no wind crust, the 
softer, more compressible snow may also provide a 
more attractive bedding medium for moose (Des 
Meules 1965). The snow gradient in the lee of 
coniferous cover also allows the moose a choice of 
snow depths in which to bed. 

The data suggests that moose bed in a manner that 
allows them to utilize radiant energy from the sun. 
Least effective coniferous cover was recorded in the 
direction of S, SE, or SW in 59% of the cases at bed 
sites (Table 5). Moose bedded at these sites could 
receive sunlight unobstructed by coniferous cover. 
The dark coat of the moose would absorb much of the 
solar radiation available. Moen (1973) pointed out 
that this solar radiation could reduce the thermal 
gradients in an animal's hair layer, thus reducing heat 



Table 4 — Directions from which moose received the best windbreaking protection while bedded, 13 January -28 Februarv 
1975 









Direction of most 


effective 


cover 






Northerly 
directions 


E 


W 




Southerly 
directions 


Total 


Frequency of 
occurrence, % 


45.1 


22.6 


15.2 




17.0 


99.9% 



Table 5 — Directions from which moose received the least windbreaking protection while bedded, 1 3 January - 28 February 
1975 







Direction in which least effective 


cover lay 






Northerly 
directions 


E W 


Southerly 
directions 


Total 


Frequency of 
occurrence, % 


13.8 


11.1 16.2 


59.0 


100.1% 



192 



The Canadian Field-Naturalist 



Vol. 92 



loss through conduction. 

In summary, it appears that residual coniferous 
cover may be an important component of the moose's 
winter range in northern Ontario mixed upland 
cutovers, as it provides thermal advantages to the 
animal when bedding. This in turn would lower the 
species' energy requirements and perhaps have 
survival value during severe winters. 

Acknowledgments 

We gratefully acknowledge the assistance in the 
field of H. R. Timmermann, Ministry of Natural 
Resources, Thunder Bay Regional Office. Financial 
support for this project was provided through the 
Conjoint Programme of the Ontario Ministry of 
Natural Resources. 



Literature Cited 

Des Meules, P. 1964. Theinfluenceof snow on the behavior 

of moose. Transactions of the Northeastern Wildhfe 

Conference 21: 51-73. 
Des Meules, P. 1965. Hyemal food and shelter of moose in 

Laurentides Park, Quebec. M.Sc. thesis. University of 

Guelph, Guelph, Ontario. 138 pp. 
Franzmann, A.W., P.D. Arneson, and J.L. Oldemeyer. 

1976. Daily winter pellet groups and beds of Alaskan 

moose. Journal of Wildlife Management 40(2): 374-375. 
McNicol, J. G. 1976. Late winter utilization of mixed 

upland cutovers by moose. M.Sc. thesis. University of 

Guelph, Guelph, Ontario. 134 pp. 
Moen, A. N. 1973. Wildlife ecology. W. H. Freeman and 

Company, San Francisco. 458 pp. 

Received 30 August 1977 
Accepted 21 December 1977 



Spring and Summer Food Habits of an Ermine (Mustela erminea) 
in the Central Arctic 



David A. Simms 



Department of Biology, York University, Downsview, Ontario M3J 1P3 



Simms, David A. 1978. Spring and summer food habits of 
Field-Naturalist 92(2): 192-193. 

Few quantitative data are available on the diet of 
the Ermine (Mustela erminea) in North America. The 
only studies of which I am aware are those of 
Hamilton (1933), Aldous and Manweiler (1942), 
Maher (1967), and Fitzgerald (1977). The following 
data are therefore of interest. 

While conducting a preliminary ecological in- 
vestigation of lemmings on the island of Igloolik 
(69°24'N, 81°49'W), off the Melville Peninsula, I 
discovered, on 9 August 1977, the active den site of an 
Ermine. After a thorough inspection of the site, 102 
scats and 13 portions of lemming bodies were 
obtained for analysis. Prey items were identified on 
the basis of hairs and feathers found in the scats and 
on dental and skeletal remains from scats and body 
parts. No attempt was made to identify bird remains 
to species and each scat was presumed to represent 
one individual prey item, unless it could be proven 
otherwise. 

The den site, measuring approximately 20 by 45 m, 
was located on a small ridge near the top of a 450-m, 
gently inclined, east-facing slope. It was quite rocky 
with numerous small limestone cavities. Vegetation 
on the site was sparse, consisting mainly of Mountain 
Avens (Dryas integrifolia) and lichen patches, with 



an Ermine {Mustela erminea) in the central Arctic. Canadian 

some mosses. Surrounding the den area was an 
extensive expanse of poorly-to-moderately developed 
Dryas-Salix and Dryas-Mchtn heath, intermixed with 
bare stretches of limestone and gravel. The nearest wet 
meadows of Carex stans and Eriophorum angusti- 
folium were, with the exception of a small patch near 
to the den measuring roughly 60 by 100 m, some 
450 m removed from the den site. 

Analysis of the fecal material and body parts 
yielded the following numbers of individual prey 
items: Collared Lemmings {Dicrostonyx torquatus), 
106; Brown Lemmings {Lemmus sibiricus), 9; birds, 
26; and insects, 1. In addition to these items, some 
plant material was found. But as this material 
occurred in such small amounts and only in some 
scats, and as none of it appeared to have been 
digested, I suspect that it had been ingested 
unintentionally. In many cases the bone fragments of 
lemmings were poorly ossified, indicating that 
juveniles constituted a substantial portion of the diet. 
Considering the availability of nestlings in the area, 
many of the birds taken by this weasel may also have 
been young. The most common small birds in the area 
were Lapland Longspurs (Calcarius lapponicus). 
Snow Buntings (Plectrophenax nivalis), Baird's 



1978 



Notes 



193 



Sandpipers {Calidhs bairdii), White-rumped Sand- 
pipers (C. fuscicollis), and the somewhat larger 
Golden Plover (Pluvialis dominica). 

The den was located in an area of rocky heath, so I 
expected that Collared Lemmings would predominate 
in the diet. This species reportedly prefers such 
habitats, at least in summer, whereas the Brown 
Lemming restricts its movements largely to wet 
meadows and adjacent areas (Banfield 1974). Despite 
these spatial arrangements, the preponderance of 
Collared Lemmings taken by this Ermine was 
surprising since Collared Lemmings appeared to be at 
a population low; I did not observe any free-ranging 
individuals during my 28 days on Igloolik. Brown 
Lemmings, although seemingly more numerous than 
the above, also appeared to be at moderately low 
densities; only 13 free-ranging individuals were 
sighted. My studies in southern Ontario (un- 
published) have shown that Ermine are capable of 
regularly traversing distances greater than 500 m. 
Brown Lemmings from the wet meadows described 
above were therefore potentially accessible to this 
Ermine. The foregoing observations on lemmings 
were substantiated by live-trapping. Twelve hundred 
trap-days, checked twice daily, yielded only four 
captures of two Collared Lemmings and 30 captures 
of 14 Brown Lemmings. Approximately 70% of the 
trapping effort was in habitats considered favorable to 
Collared Lemmings. Custom-made wooden live-traps 
were used to trap lemmings. According to local 
observers, lemming populations on Igloolik have been 
relatively low since the high of 1970. The scarcity of 
Snowy Owls (Nyctea scandiaca) this year (1977) 
further indicated relatively low lemming populations. 
Only one owl was sighted during the entire summer. 
More were seen the previous year (M. C. Lewis, 
personal communication). The only other lemming 
predator noted on the island was the Long-tailed 
Jaeger (Stercorarius longicaudus). 



For comparison, 30 Snowy Owl pellets of undeter- 
mined age, from a variety of locations on the island, 
were collected and examined. These contained the 
following numbers of prey items: Collared Lemmings, 
89; Brown Lemmings, 12; birds, 4. Both predators 
must, by necessity, exploit much the same food 
sources as little else is available. Direct comparisons in 
this case, however, are not valid as the owl pellets were 
from previous years and only one individual Ermine 
was involved. It is quite probable that Ermine hving in 
or near wet meadows exploit Brown Lemmings to a 
much greater extent than did the individual discussed 
here. 

The presence of the Ermine whose food habits are 
described herein, and one other individual observed 
approximately 5 km from the described den site, 
shows that Ermine are able to persist in areas where 
lemming densities are relatively low. 

I thank D. M. Cameron and D. J. McQueen for 
critically reviewing the manuscript. Partial funding 
for this endeavor was provided through M. C. Lewis. 

Literature Cited 

Aldous, S. E. and J. Manweiler. 1942. The winter food 
habits of the short-tailed weasel in northern Minnesota. 
Journal of Wildlife Management 23: 250-255. 

Banfield, A. W. .F 1974. The mammals of Canada. Uni- 
versity of Toronto Press, Toronto. 438 pp. 

Fitzgerald, B. M. 1977. Weasel predation on a cyclic 
population of the montane vole (Microtus montanus) in 
California. Journal of Animal Ecology 46: 367-397. 

Hamilton, W. J., Jr. 1933. Weaselsof New York. American 
Midland Naturalist 14: 289-344. 

Maher, W. J. 1967. Predation by weasels on a winter 
population of lemmings. Banks Island, Northwest Ter- 
ritories. Canadian Field-Naturalist 81: 248-250. 



Received 22 November 1977 
Accepted 26 January 1978 



Red Squirrels, Tamiasciurus hudsonicus, in the Salmonier River 
Valley, Newfoundland 



R. Ian Goudie 



R.R. 1, St. Catherines, Salmonier, St. Mary's Bay, Newfoundland AOB 2M0 

Goudie, R. Ian. 1978. Red Squirrels, Tamiasciurus hudsonicus, in the Salmonier River valley, Newfoundland. Canadian 
Field-Naturalist 92(2): 193-194. 



Introduced Red Squirrels {Tamiasciurus hud- 
sonicus) have become established in three isolated 
parts of insular Newfoundland. The first two 
introductions, on the Great Northern Peninsula and 



on Camel Island, Notre Dame Bay, and the establish- 
ment of populations resulting from them have been 
described by Northcott (1974) and Payne (1976). This 
note reports the third introduction. 



194 



The Canadian Field-Naturalist 



Vol. 92 




Figure I. Red Squirrel observations in Salmonier River 
valley, Newfoundland. Insert top left: study area 
near St. Catherine's on insular Newfoundland. 

Staff of the Newfoundland Wildlife Division, 
Department of Tourism, released four male and seven 
female Red Squirrels, captured from the Northern 
Peninsula population, at the Salmonier Wildlife Park 
(47° 16'N,53° I7'W) on the Avalon Peninsula in July 
1974 (Minty, personal communication). 

There were three sightings by me and infrequent 
ones by other local residents during the fall and winter 
of 1974. These were mostly restricted to sheltered 
valleys in the area of the confluence of the Back River 
and the Salmonier River (locally known as the Back 
River Hills, 13 km southwest of the introduction site 
(Figure 1). Observations in the Salmonier River valley 
during the fall of 1975 indicated the presence of the 
squirrels; however, the population density did not 
appear to have increased substantially during 1975 (I 
recorded six sightings from 16 10-km transects along 
Salmonier River valley). The Red Squirrel sightings 
increased dramatically during the fall and winter 
within the river valley basin. The recording of 14 
sightings from the same transects during the winter of 
1976-77 indicated a population of no fewer than 200 
individuals, centered in the area of the confluence of 
the Back River and Salmonier River. These observa- 
tions indicate the population is spreading, at least 
within the confines of the boreal forest cover. Present 
sighting data indicate the population has a distribu- 
tion of some 50 km2 with sightings up to 15 km 



southwest of the release site. 

The general area of confluence of the Back River 
and the Salmonier River is very rich in forest growth 
with north-facing slopes dominated by Balsam Fir 
(Abies balsamea) - Yellow B'\rch{Betula luted) forests 
with a dense ground cover of ferns (Dryopteris 
spinulosa), scattered mosses, and herbs. South-facing 
slopes lack the high proportion of hardwood species 
prominent in the aforementioned cover and are 
covered by Balsam Fir forests with a dominant moss 
ground cover of Hylocomium splendens, Pleurozium 
schreberi, and Rhytidiadelphus loreus. Both slopes in 
this lower section of the Salmonier River valley 
support rich forest cover in differing stages of 
succession. The productivity of this general area may 
account for the concentration of the Red Squirrel 
population in this vicinity. 

1 predict that Red Squirrels will extend their range 
radially within the boreal forest of the Avalon 
Peninsula. Forests like that of Salmonier River valley 
are abundant on well drained slopes, terraces, and 
hummocks within the Boreal Forest Ecoregion 
(Meades 1973). Sections of forest are interspersed 
with extensive areas of raised bog and slope bog 
formation (Wells 1 976). 1 doubt that these bogs will be 
a barrier to squirrel dispersal. 

The present relatively low number of mammalian 
predators such as Red Foxes ( Vulpes vulpes). Lynx 
{Felis lynx), and Mink {Mustela vison) within the 
Salmonier River valley may have favored a rapid 
increase in Red Squirrel density. Red Squirrels are a 
welcome addition to the island's fauna since small 
mammal prey species are limited to Meadow Voles 
{Microtus pennsylvanicus) and Masked Shrews 
{Sorex cinereus). The endangered Newfoundland sub- 
species of Marten (Martes americana atrata) may 
eventually utilize Red Squirrels as its major prey 
species as is the case on the adjacent mainland. The 
result of the overall introduction of Red Squirrels to 
Newfoundland may help catalyze the expansion of 
Martens there. 

Literature Cited 

Meades, W.J. 1973. A phytosociological classification of 
the Avalon Peninsula heath, Newfoundland. M.Sc. thesis. 
Memorial University of Newfoundland, St. John's. 
249 pp. 

Northcott, Tom H. 1974. The land mammals of insular 
Newfoundland. Newfoundland Department of Tourism, 
Wildlife Division. 90 pp. 

Payne, Neil F. 1976. Red squirrel introduction to New- 
foundland. Canadian Field-Naturalist 90(1): 60-64. 

Wells, Edward Doyle. 1976. A classification of peatlands in 
eastern Newfoundland. M.Sc. thesis. Memorial Uni- 
versity of Newfoundland, St. John's. 201 pp. 



Received 16 May 1977 
Accepted 13 January 1978 



1978 



Notes 



195 



Flycatching by Male Song Sparrows, Melospiza melodia 



James N. M. Smith 



Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1W5 

Smith, James N. M. 1978. Flycatching by male Song Sparrows, Melospiza melodia. Canadian Field-Naturalist 92(2): 
195-196. 



Tompa (1963) observed that Song Sparrows on 
Mandarte Island, British Columbia, occasionally flew 
high into the air to capture insects, much like typical 
tyrannid or muscicapid flycatchers. During the 1975 
breeding season on Mandarte Island, British Colum- 
bia, I noticed that male Song Sparrows seemed to 
flycatch more than females. By 1976 and 1977, 1 had 
marked all resident breeding Song Sparrows and was 
therefore able to watch known individuals to see 
whether males really attacked flying insects more 
often. 

Between 7 April and 2 July 1976 and 31 March and 
2 June 1977. 1 collected records of flycatching by Song 
Sparrows of known sex during regular census walks 
and during nest watches. I spent equal time observing 
males and females during nest watches, when both 
were feeding nestlings, but encountered males slightly 
more often during census walks because of their more 
frequent presence on high perches. 

I observed flycatching most often on calm warm 
days in April. A sparrow typically flew from a perch 
on top of a l-to3-m-high shrub and rose up to 10 min 
the air. Several lunges, accompanied by snapping of 
the beak, were often made at the prey, which was often 
an asilid fly. The reason that most flycatching was 
observed in April may be that this was the peak 
activity time for asilids. Another possible explanation 
is that Song Sparrows are less inclined to leave their 
territories to forage in undefended parts of the island 
at this time. Tompa (1963) in fact found that Song 
Sparrows fed outside their territories less often in 
April than in any month during the non-breeding 
season, but he did not collect information during 



May, June, or July. Although an accurate record of 
successful sallies was not made, most flycatching 
attempts seemed to be successful. In 1976, males 
accounted for 88% of the individuals flycatching and 
96% of the attempts at flycatching; in 1977, the 
corresponding percentages were 75% and 79% (Table 
1). Although flycatching by females was clearly more 
common in 1977 than 1976, there were many more 
flycatching attempts by males than females within 
each year. I cannot explain why females were 
observed flycatching more often in 1977 than 1976. 

How can the sexual differences in flycatching 
frequency be explained? One possibility is that male 
Song Sparrows, which have longer wings than females 
(Knapton 1973), are more efficient in flycatching. 
Wing loading (Greenewalt 1975) is an index of energy 
use during forward flight; the lower the wing loading, 
the more manoeuvrable the bird. Specialized fly- 
catchers have very low wing loadings (Greenewalt 
1975). I measured the wing areas and weights of 11 
male and 8 female Song Sparrows during August 1977 
and calculated the mean wing loadings for each sex. 
Male wing loading (0.35 g/cm-) did not differ 
significantly (P^O. 10, Mest, df = 17) from that of 
females (0.38 g/cm-). Males and females thus seem 
similar in the morphological trait most likely to 
influence flycatching. 

I believe that a behavioral difference between the 
sexes during the breeding season is a more important 
cause of the sex difference in flycatching. Male Song 
Sparrows spend much of their time on high perches 
within their territory, either singing or looking for 
intruders (Nice 1943). In contrast, females seldom use 



Table 1 — Population sizes, numbers of individuals flycatching, and frequency of flycatching attempts by male and female 
Song Sparrows on Mandarte Island, British Columbia, in the springs of 1976 and 1977 



Sex 



Males 



Females 



Year 
1976 
1977 
1976 

1977 



Minimum number 
of birds present 

42 

49 

30 

45 



Number of individuals Number of instances 
seen flycatching of flycatching 



29 

33 

4 

11 



89 

181 

4 

49 



196 



The Canadian Field-Naturalist 



Vol. 92 



high perches, often move about inside shrub thickets, 
and spend much time incubating. I suggest that this 
difference causes males to see potential flying insect 
prey more often than do females, and enables them to 
launch aerial attacks from a high perch with less 
energy expenditure. Many of the female flycatching 
flights observed in 1977 were carried out from low 
perches and involved only very short flights. 

Jon S. Greenlaw (personal communication) has 
noted a similar sex difference in flycatching fre- 
quency by Rufous-sided Towhees {Pipilo erythro- 
phthalmus) in northeastern USA. Hence sex dif- 
ferences in foraging may be an incidental conse- 
quence of spatial separation of male and female 
activities, and not an evolved mechanism to avoid 
intersexual competition. 

I thank J. Russell, N. A. M. Verbeek, R. Zach, and 
J. Myers for help with field work. Verbeek, R. W. 
Knapton, R. D. Montgomerie, and J. S. Greenlaw 
offered helpful comments on an earlier draft of the 
paper and Greenlaw kindly allowed me to quote his 
unpublished observations. The research was sup- 



ported by the National Research Council of Canada. I 
thank the Tsawout and Tseycum Indian Bands for 
allowing me to work on their island. 

Literature Cited 

Greenewalt, C. H. 1975. The flight of birds. The significant 
dimensions, their departure from the requirements for 
dimensional similarity and the effect on flight aero- 
dynamics of that departure. Transactions of the American 
Philosophical Society 65: 1-67. 

Knapton, R. W. 1973. Some ecological aspects of social 
behaviour in the Song Sparrow, Melospiza melodia. 
M.Sc. thesis. University of British Columbia, Vancouver. 

Nice, M. M. 1943. Studies in the life history of the Song 
Sparrow. Part II. The behavior of the Song Sparrow and 
other passerines. Transactions of the Linnaean Society of 
New York 6: 1-329. 

Tompa, F. S. 1963. Factors determining the numbers of 
Song Sparrows, Melospiza melodia (Wilson), on Man- 
darte Island, B.C. Ph.D. thesis. University of British 
Columbia, Vancouver. 

Received 22 November 1977 
Accepted 16 January 1978 



Feeding at a Trap-net by Black-crowned Night Herons 



A.L.A. MiDDLETON 



Department of Zoology, University of Guelph, Guelph, Ontario NIG 2W1 

Middleton, A.L.A. 1978. Feeding at a trap-net by Black-crowned Night Herons. Canadian Field-Naturalist 92(2): 196. 



At dusk on 10 July 1971, at Sarnia, Ontario five 
Black-crowned Night Herons (Nycticorax nyctico- 
rax) flew in a northeasterly direction from the trees 
behind me out over the calm surface of Lake Huron. I 
followed their flight with binoculars and was sur- 
prised to see them descend towards a well-marked 
(flagged buoys) commercial trap-net, located ap- 
proximately 300 m offshore in 7 m of water. As the 
birds' bodies remained clear of the water, they must 
have landed on the net or on the leads running from 
shore. The five birds were dispersed around the net 
and its leads, and each seemed to be engaged in 
catching prey. Unfortunately the light was too dim to 
determine whether any prey was captured. 

I repeated my observations on the following 
evening, when weather conditions were similar. At 
dusk five herons again flew from the trees to the net 
and apparently began fishing. Once more I was unable 
to identify the prey or to determine the capture rate. 
No further observations were made. 

Generally herons are accepted to be shallow-water 
feeders. Recent reports, however, indicate that both 
Black-crowned Night Herons (Crawford, R.D. 1976. 



Iowa Bird Life 46: 20-21) and Great Blue Herons 
{Ardeaherodias) {Godin,i.i. 1977. Canadian Field- 
Naturalist 9 1 : 88-90) will resort to open-water feeding 
under certain circumstances. Although I could not 
establish the identity of the prey, several species of 
small fishes would have been available to the herons 
(H.R. MacCrimmon, personal communication). Ad- 
ditionally, the fact that the herons flew directly to the 
net on two successive evenings suggests that they knew 
its location and must have had some previous success 
in capturing prey at the net. Finally, the birds were not 
swimming but were apparently standing on the mesh 
of the net or the lead lines, from which they could dart 
at fish either trapped in the net or swimming close to 
the surface. 

As suggested by Crawford (op. cit.), open-water 
feeding by Black-crowned Night Herons may be a 
more commonly used feeding behavior than has been 
previously recognized. 



Received 30 September 1977 
Accepted 7 December 1977 



1978 



Notes 



197 



Occurrence of Carex careyana in Canada 



Peter W. Ball 

Department of Botany, Erindale College, University of Toronto, Mississauga, Ontario L5L 1C6 

Ball, Peter W. 1978. Occurrence of Carex carevana in Canada. 
Canadian Field-Naturalist 92(2): 197-198. 

Carex careyana is a rare sedge in Canada. It was 
first recorded by Klugh (1906) from Guelph, Ontario. 
MacKenzie (1935) and Soper (1949) also mentioned 
the occurrence of this species in Ontario, but both of 
these records seem to have been based on the 
specimens collected by Klugh. The species has also 
been recorded from one locality in southern Quebec 
(near Sweetsburg) cf., Raymond 1941), but no 
confirmatory specimens have been seen, and Rouleau 
(1946) throws some doubt on its occurrence in that 
province. Boivin (1967) excluded C. careyana from 
the Canadian flora, but in a personal communication 
(1976), he stated that he has subsequently traced ma- 
terial collected by Klugh in 1905 and 1906 in the her- 
baria of Queen's University, Kingston (QK) and the 
University of Guelph (OAC). None of these specimens 
give any precise details of the locality, other than 
Guelph, but a previously untraced specimen in the 
herbarium of the National Museum of Canada (CAN) 
gives the location as Dairy Bush, Ontario College of 
Agriculture, Guelph. 

In addition to the locality discovered by Klugh the 
species has previously been collected from two other 
localities in southern Ontario. Curiously enough, 
both collections were made by A. A. Wood in 
Middlesex County in 1934. One, correctly determined 
as C. careyana, was from Strathroy, the other from 
Poplar Hill about 10 km east of Strathroy. This second 
specimen was originally determined as C. platyphylla, 
but this determination was corrected by Boivin in 
1974. Both specimens are preserved in the herbarium 
of the Biosystematics Research Institute, Ottawa 
(DAO). 

This investigation was prompted by the discovery 
of a fourth locality for this species in Ontario. This 
locality, in Halton County, about 3 km south of 
Rockwood is only about 12 km from Klugh's original 
locality. The known distribution of C careyana in 
Canada is shown in Figure 1. The clustering of the 
locations into two centers about 150 km apart, and 
each 150 km or more from any locality in the United 
States is a conspicuous feature of the map. This map 
should be compared with that given by Voss ( 1 972) for 
this species in Michigan. Although the species is not 
common in Michigan it is found in about half of the 
counties in the southern half of the state. This suggests 
that the species, although rare in Ontario, is probably 




Figure 1. The distribution of Carex careyana in Ontario. 

much more widespread in the province but has been 
overlooked. This explanation is supported by the 
manner in which the new locality was discovered. It 
was first collected there in 1966 by B.W. Davies, who 
at the time was a graduate student working under the 
supervision of P.P. Maycock (Maycock, Stand 1 1 14). 
Owing to the lateness of the season, the species could 
not be identified in the field, so a specimen was 
collected and subsequently tentatively determined as 
C. laxiculmis, another member of the section 
Laxiflorae. Whilst checking material of section 
Laxiflorae the anomalous characters of this speci- 
men were noted and eventually a single perigynium 
was found on the withered culm, which led to a tenta- 
tive re-determination as C. careyana by A. A. Rezni- 
cek and the author. This was confirmed in 1974 when 
the locality was rediscovered and good material of the 
species was collected. 



198 



The Canadian Field-Naturalist 



Vol. 92 



Carex careyana is a sedge that is relatively easy to 
recognize. Although a member of the section 
Laxiflorae which, as a whole, can be difficult to 
distinguish from several other sections, C. careyana is 
a member of a small group within the section which 
has very broad evergreen rosette leaves, and culm 
leaves with very reduced blades. Besides C careyana, 
the other species in the group in Canada are C. 
plantaginea and C. platyphylla. Carex platyphylla can 
be recognized throughout the year by the glaucous or 
gray-green rosette leaves which are completely lacking 
in red or purple color. Carex plantaginea and C. 
careyana have bright green basal leaves which have 
strong reddish-purple color at the base. Unfortunate- 
ly, it does not seem possible to distinguish reliably 
between these two species in the vegetative state. 
Carex careyana has the basal leaves 8-17 mm wide, 
whilst C. plantaginea has the basal leaves 12-30 mm 
wide, these being proportionally much broader. From 
about the middle of May to the end of June, when 
fruiting culms are present on these species, they can be 
readily separated. Carex careyana has short green 
blades on the culm leaves which also have purple 
sheaths, and the perigynia are 5-6.5 mm long. Carex 
plantaginea has culm leaves which are completely 
purple and almost completely devoid of a blade, 
whilst the perigynia are only 3^.5 mm long. Carex 
platyphylla, besides lacking all purple color, has the 
perigynia only 3^.5 mm long. Other species which 
might be confused with C careyana are C. albursina, 
C laxiflora, C. laxiculmis and other members of the 
section Laxiflorae that sometimes have broad basal 
leaves. All of these species, however, have little or no 
purple coloration, have well-developed blades on the 
culm leaves, and have the perigynia less than 5 mm 
long. Species in several other sections have dark 
purple color on the basal leaves but in all cases the 
blades are much narrower than those of C. careyana. 

Ecologically the three species of this group are very 
similar. The Halton County location for C. careyana 
is a small area dominated by large individuals of Acer 
saccharum (Sugar Maple). The stand is near the top of 
a slope with a northern aspect. It has a fairly rich 
ground flora with Phlox divaricata. Allium tricoc- 
cum, Schizachne purpurascens, and nine other species 
of Carex all prominent at the time that C careyana is 
in fruit. Carex careyana does not occur throughout 
the stand, but is found on the crest of a ravine at the 
northern edge. The sides of the ravine are covered by a 
stand of Thuja occiden talis (White Cedar), Abies 
halsamea (Balsam Fir), Picea glauca (White Spruce), 
and Betula papyri/era (Paper Birch). It is not unusual 
to find C platyphylla in similar situations. 

The available evidence suggests that C. careyana 
should be looked for throughout southern Ontario 
and the extreme southern part of Quebec. It is 



confined to hardwood forests that have a compara- 
tively rich ground flora, but it seems to occur both on 
rocky limestone and on sandy substrates. 

Specimens Examined 

Halton County: 1 Vi m. (2.5 km) west of Crewsons Corners on 

Highway 7, then 1 mi (1.7 km) south. Stand 1 1 14, 28 June 

1966, B.W. Davies (Herb. P.P. Maycock!). About 2 mi (3.3 

km) south of Rockwood, 20 June 1974. P.W. Ball 10374 

(TRTE!). 

Wellington County: Guelph, 28 May 1905, 8 June 1905, 1 

May 1906, 4 May 1906. A.B. Klugh (QK, Photo DAO!). 

Guelph, 28 June 1905, A.B. Klugh (OAC, Photo DAO!). 

Dairy Bush, OAC Guelph, 30 April 1906, A.B. Klugh 

(CAN!). 

Middlesex County: Poplar Hill, rich sandy woods and 

banks, 14 May 1934. A. A. Wood (DAO!) (sub C. platy- 

phrlla). Strathroy, Conley's Wood, 29 May 1934, A. A. 

Wood (DAO!). 

I thank B. Boivin, Biosystematics Research Insti- 
tute, Ottawa and P. Maycock, University of Toronto, 
for making the unpublished data available to me. This 
work was financed by NCR grant A6494. 

Literature Cited 

Boivin, B. 1967. Enumeration des plantes du Canada. 
Naturaliste Canadien 94: 471-528. 

Klugh, A.B. 1906. The Cyperaceae of Wellington County. 
Ontario Natural Science Bulletin 2: 38^1. 

MacKenzie, K.M. 1935. North American flora 18. Cyper- 
aceae tribe 1, Cariceae part 5. New York Botanical 
Garden, New York. pp. 244-260. 

Raymond, M. 1941. Notes sur la distribution geographique 
de quelques Carex. Annales de I'ACFAS 7: 105-106. 

Rouleau, E. 1964. In Flore Laurentienne. Edition 2. By 
F. R. Marie-Victorin. Universite de Montreal, Montreal. 
925 pp. 

Soper, J.H. 1949. The vascular plants of southern Ontario. 
University of Toronto, Toronto. 95 pp. 

Voss, E.G. 1972. Michigan flora. Part 1. Cranbrook Insti- 
tute of Science, Bloomfield Hills, Michigan. 488 pp. 

Received 14 June 1977 
Accepted 5 December 1977 



Addendum 

A further locality for C. careyana in Halton county 
has recently been detected. It is about 12 km south of 
the new locality reported above. 
Halton County. Halton Forest, Currie Tract, near 

Campbellvilie, 14 May 1977. P. Catling (TRT!) 

(sub C. laxiflora). 

30 March 1978 



1978 



Notes 



199 



Wheatears and a Magnolia Warbler in Southern Davis Strait 

Stuart I. Tingley 

Canadian Wildlife Service, P.O. Box 1590, Sackville, New Brunswick EOA 3C0 



Tingley, Stuart I. 1978. Wheatears and a Mangolia Warbler in southern Davis Strait. Canadian Field-Naturalist 
92(2): 199. 



While conducting biological investigations aboard 
a seismic vessel (RV Kirsten Bravo) in the Cumber- 
land Sound region of Davis Strait in late August and 
September 1976, I recorded migrant passerines seen 
near to, or landing on, the ship. Two records are of 
special interest. 

Between 2400, 31 August and 0430 GMT, 1 
September, I recorded a total of seven or eight 
Wheatears (Oenanthe oenanthe) circling the ship in 
the cold rain which had fallen throughout the day. 
Several of the birds landed on the ship for periods 
ranging from a few seconds to a half hour. Many birds 
appeared quite exhausted and I was able to capture 
and photograph one individual (photo on file at 
National Museum of Natural Sciences). I also 
photographed a second similar individual perched on 
a railing. Wing measurement of the captured bird was 
101.5 mm., confirming its subspecific identity as O. 
oenanthe leucorhoa, the breeding form of eastern 
Canadian Arctic and sub-arctic regions as well as 
Greenland (Stejneger 1901). Although light condi- 
tions were poor, it appeared that two birds had well- 
defined ear patches indicative of adult males, the rest 
of the birds probably being adult females or im- 
matures. The ship's position during the period of 
observation was roughly 60° lO'N, 59° 15'W. 

These birds probably originated in the eastern 
Canadian arctic and sub-arctic regions as well as 
grounds in the Old World via Greenland. Wheatears 
from the northern part of their Canadian range 
apparently use Greenland as a stopping-off place in 
their fall migration while those in the southern part of 
their range may make a direct non-stop flight across 
the Atlantic (Salomonsen 1951; Todd 1963). Snow 
(1953) reports two fall sightings of Wheatears from 
ships in southeastern Davis Strait which were also 
probably Canadian birds. The date of my observation 
falls within normal migration dates for Canadian 
Wheatears as recorded by Snyder (1957), though 
Wynne-Edwards (1952) did not record this species in 
central and southeastern Baffin Island after 1 1 August 
during his study of that area in 1950. 

Around 1500 GMT, 15 September, I discovered an 
immature Magnolia Warbler {Dendroica magnolia) 
flying about the cable room on the lower deck. The 
bird was extremely wary and flew about the room 



searching frantically for an escape route, which led 
me to believe that the bird had only recently arrived. 
The ship's position at the time of, and for 12 h before 
the observation was 62°55'N, 60°23'W. Godfrey 
( 1 966) reports Magnolia Warbler possibly breeding as 
far north as Hamilton Inlet, Labrador, but does not 
mention any records from the eastern Canadian 
Arctic. Surprisingly, Salomonsen (1967) reports two 
records of this warbler for Greenland, one in Godthab 
District sometime in 1875, and a second in Sukker- 
toppen District on I October 1950. 

Other migrant passerines recorded on the cruise 
in mid-southern Davis Strait were Water Pipit 
(Anthus spinoletta). Hoary Redpoll {Carduelis hor- 
nemanni). Common Redpoll {Carduelis flammea), 
Lapland Longspur {Calcarius lapponicus), and Snow 
Bunting (Plectrophenax nivalis). 

These observations were made during environ- 
mental investigations sponsored jointly by Imperial 
Oil Ltd. and the Canadian Wildlife Service. Special 
thanks to D.N. Nettleship for critically reading the 
manuscript and making many helpful suggestions. 



Literature Cited 

Godfrey, W. E. 1966. The birds of Canada. National 
Museum of Canada Bulletin 203. 428 pp. 

Salomonsen, F. 1951. Gronlands fugle. The birds of Green- 
land. Ejnar Munksgaard, Kobenhavn. 604 pp. 

Salomonsen, F. 1967. Fuglene pa Gronland. Rhodos, 
Kobenhavn. 343 pp. 

Snow, D. W. 1953. The migration of the Greenland 
Wheatear. Ibis 95(2): 376-378. 

Snyder, L. L. 1957. Arctic birds of Canada. University of 
Toronto Press, Toronto. 310 pp. 

Stejneger, L. 1901. On the Wheatears (Saxicola) occurring 
in North America. Proceedings of the United States 
National Museum 23. pp. 473-481. 

Todd, W. E. C. 1963. Birds of the Labrador Peninsula and 
adjacent areas. University of Toronto Press and Carnegie 
Museum, Toronto. 819 pp. 

Wynne-Edwards, V. C. 1952. Zoology of the Baird Ex- 
pedition (1950). 1. The birds observed in central and 
southeast Baffin Island. Auk 69(4): 377-378. 

Received 1 June 1977 
Accepted 20 December 1977 



200 



The Canadian Field-Naturalist 



Vol. 92 



Records of the European Skipper in Newfoundland 



Bernard S. Jackson 

Oxen Pond Botanic Park, Memorial University, St. John's, Newfoundland AlC 5S7 

Jackson, Bernard S. 1978. Records of the European Skipper in Newfoundland. Canadian Field-Naturalist 92(2): 200. 



The European Skipper, Thymelious lineo/a (Lepi- 
doptera: Hesperiidae), was introduced to North 
America in or before 1910 in the region of London, 
Ontario (Alexander B. Klots. 1951. A field guide to 
the butterflies of North America, east of the Great 
Plains. Houghton Mifflin Company, Boston). It has 
not been previously reported from Newfoundland. 

The insect collection at the Agricultural Research 
Station, St. John's, contains a specimen taken on 24 
July 1975 from the radiator grill of a vehicle that had 
recently arrived in St. John's, from mainland Canada 
(R. F. Morris, personal communication). This speci- 
men was probably hit before the vehicle entered 
Newfoundland. The following are my reports of 
observations of the species in Newfoundland. 

At 1530 hours on 3 August 1976 a European 
Skipper was observed feeding from the flowers of 
Fireweed (Epilohium anguslifolium), against the 
carpark in the Oxen Pond Botanic Park, St. John's, 
Newfoundland (47°34'N, 52°43'W). A subsequent 
check of nearby grassy areas revealed a total of 1 1 
freshly emerged individuals. Specimens were seen 
intermittently over the following 2 weeks and a pair 
was collected for the insect collections at the 
Agricultural Research Station, St. John's. The last 
sighting for the year was of three individuals on 19 
August 1976. 

It is possible that these individuals originated from 
eggs laid in the general area the previous year, but the 



origin of the gravid female(s) is (are) unknown. No 
plants with a known or suspected capability as a host 
for the larvae of this skipper were brought into the 
park from outside sources within the previous 2 years. 
An entomologist spent the greater part of the 1975 
season collecting in the area without finding a single 
specimen of this species; this would suggest that very 
few were present at that time. 

Independent searches, by myself and R. F. Morris, 
of adjacent rough meadows and grassy roadsides, up 
to a distance of 100 m from the original discovery site 
during the period the skippers were observed, failed to 
reveal any further specimens. 

Nevertheless during late July and early August 1977 
European Skippers were again sighted and were 
common around the discovery site. On occasion it was 
possible to view 12 on the wing simultaneously. 

On 26 July 1977, R. F. Morris (personal com- 
munication) discovered European Skippers at a site 
approximately 10 km north of Bishops Falls, New- 
foundland (49°0rN, 55°30'W). Three specimens were 
collected for the insect collections at the Agricultural 
Research Station, St. John's. 

The populations observed at both sites probably 
originated from the drift movement of adult insects 
entering the area from mainland Canada. 



Received 4 April 1977 

Updated and accepted 6 January 



1978 



First Record of the Ancient Murrelet for Alberta' 

D. Vaughn Weseloh and Linda McKeane Weseloh 

Provincial Museum of Alberta, 12845-102 Avenue, Edmonton, Alberta T5N 0M6 

Present address: Department of Ornithology, Royal Ontario Museum, Toronto, Ontario M5S 2C6 

Weseloh, D. Vaughn and Linda McKeane Weseloh. 1978. First record of the Ancient Murrelet for Alberta. Canadian 
Field-Naturalist 92(2): 200-201. 



On 25 October 1975 at 1435 hours, we observed 
and later captured a winter-plumaged Ancient 

'Provincial Museum of Alberta Natural History Contribu- 
tion Number 41. 



Murrelet, Synthliboramphus anliqiium. The bird was 
sighted just east of Edmonton in the North 
Saskatchewan River. We observed the bird, which 
appeared to be very weak, for 5-10 min, during which 



1978 



Notes 



201 



time it drifted with the current for about 50 m, then 
dragged itself onto shore. After watching the 
seemingly exhausted bird for another 2-3 min, we 
captured it with only minimal effort and photo- 
graphed it. 

On our return to Edmonton, we showed the bird to 
Bob Lister, Eric Tull, Steve Johnson, John Richard- 
son, Terry Thormin, Gary Searing, and Larry 
Patterson. By 1930 hours, the bird appeared much 
weaker and it had died by 2000 hours. It is now 
preserved as specimen #Z75.92.1 in the Provincial 
Museum of Alberta. 

Inland appearances of the Ancient Murrelet are not 
exceptional. E. A. Munger (1965. Inland wanderings 
of the Ancient Murrelet. Wilson Bulletin 77: 
235-242) and N. A. M. Verbeek(1966. Wanderings of 
the Ancient Murrelet: some additional comments. 
Condor 68: 510-51 1) have discussed the phenomenon 
at length and show that inland sightings of this species 
usually occur during late October and November with 
a secondary peak in March. These periods of inland 
occurrence correspond to the autumn and spring 
migration periods, respectively, of this North Pacific 
alcid. Both those authors report that autumn records 



are often coupled with onshore winds and poor 
visibility during Pacific storms. They speculate that 
the route of travel from the coast of inland-occurring 
birds is probably southeasterly, representing gradual 
displacement, rather than due west to east. 

For a full week prior to the Edmonton murrelet 
sighting, weather maps for the British Columbia coast 
showed strong westerly winds and snow showers, 
circumstances ideal for an easterly displacement of 
Ancient Murrelets migrating southward. The dura- 
tion of these weather factors coupled with the physical 
condition of the bird when found, lead us to believe 
that this individual may have been in the North 
Saskatchewan River, or at least inland, for some time 
and/or distance. The bird, a male, weighed 122 g 
(after freezing), whereas normal weight for Ancient 
Murrelets is 200-210 g (Spencer Sealy, personal 
communication). 

This is the first record of the Ancient Murrelet, or 
any member of the family Alcidae, for Alberta. 



Received 28 October 1976 
Accepted 13 January 1977 



House Sparrows Nesting near a Swainson's Hawk Nest 



W. Bruce McGillivray 



Museum of Natural History, University of Kansas, Lawrence, Kansas 66045 



McGillivray, W. Bruce. 
201-202. 



1978. House Sparrows nesting near a Swainson's Hawk nest. Canadian Field-Naturalist 92(2): 



Scattered reports describe close nest associations of 
passerines and raptors (Robson 1955; Rotschild 1959; 
Brown and Amadon 1968; Garber 1972). Bent (1937) 
noted that small birds, typically the Western 
Kingbird (Tyrannus verticalis) and Northern Oriole 
{Icterus galbula), will occasionally nest near a 
Swainson's Hawk (Buteo swainsoni) nest. Normally 
the cohabitant builds in the same tree; however, it will 
periodically incorporate its nest into that of the hawk. 

While studying House Sparrow (Passer domesti- 
cus) demography, I found three sparrow nests within 
3 m of an active Swainson's Hawk nest. The site was 
discovered 5 August 1977 in the vicinity of Conrich, 
Alberta, 5 km east of Calgary, and observed until 10 
August. The raptor nest was 8 m high in a dead 
balsam popular (Populus balsamifera). One sparrow 
nest was built into the bottom of the B. swainsoni nest, 
another 2 m away was in the same tree, and the third 



was at the same level, 3 m distant in an adjacent tree. 
The hawk's nest contained two juveniles, aged 20-25 
days, that occasionally leaned over the edge to observe 
the movements of the nest beneath theirs. All three 
sparrow nests were active; two held nestlings and the 
other was being repaired. In each case the adults were 
regularly visiting these nests. The landowner informed 
me that a pair of Swainson's Hawks used the same 
location in 1976, confirming the existence of a nest 
structure throughout the period of sparrow nest-site 
selection. 

Brown and Amadon (1968) consider doubtful the 
possibility that benefit accrues to weaverbirds of the 
genera Malimbus and Ploceus that nest near raptors. 
This places my observations in an interesting context. 
First, tree-nesting House Sparrows throughout the 
study area almost exclusively utilized coniferous trees. 
The sparrow nest in the bottom of the hawk nest was 



202 



The Canadian Field-Naturalist 



Vol. 92 



protected from adverse weather, but the other two 
were exposed and vulnerable. Secondly, no other 
House Sparrow nests were found in the woodlot 
surrounding the nest tree, the nearest being 200 m 
distant in a farm structure. The restricted distribution 
and atypical situation of Passer nests implies 
association by choice. In addition, a lowering of 
reproductive output as a consequence of nest 
exposure (Murphy 1977) would be offset if nestling 
losses and adult mortality from predators were 
reduced. The diet of the Swainson's Hawk consists of 
small rodents, insects, and only infrequently birds 
(Bent 1937; Godfrey 1966). House Sparrows in the 
area were observed to suffer nestling mortality from 
Black-billed Magpies (Pica pica); and probably 
Common Crackles (Quiscalus quiscula). These birds 
and small raptors may be excluded from the 
immediate nest area by adult Swainson's Hawks. This 
protection could account for the attractiveness of 
otherwise structurally inadequate nest sites. 

Support for this research was given by NSF grant 
BMS-76-02225. Helpful discussions were held with 



Richard F. Johnston, Peter E. Lowther, and John T. 
Paul, Jr. 

Literature Cited 

Bent, A. C. 1937. Life histories of North American birds of 

prey. United States National Museum Bulletin 167. 
Brown, L. and D. Amadon. 1968. Eagles, hawks, and 

falcons of the world. McGraw-Hill, New York, New York. 
Garber, D. P. 1972. Osprey nesting ecology in Lassen and 

Puma Counties, California. M.Sc. thesis, California State 

University, Humboldt. 
Godfrey, W. E. 1966. The birds of Canada. National 

Museum of Canada Bulletin Number 203. 
Murphy, E. C. 1977. Breeding ecology of House Sparrows. 

Ph.D. dissertation, University of Kansas, Lawrence. 
Robson, R. W. 1955. Tree Sparrow's nest built into 

occupied Buzzard's nest. British Birds 48: 189. 
Rotschild, E. V. 1959. Joint nesting of sparrows and 

predatory birds in desert. Zoologicheskii Zhurnal 38: 

935-938. (Original in Russian; only English title and 

summary read.) 

Received 4 November 1977 
Accepted 7 December 1977 






News and Comment 



Editor's Report for 1977 



We are particularly pleased with the reliable and 
pleasant service we have received from our printer. 
The issues of The Canadian Field- Naturalist printed 
by M.O.M. Printing in Ottawa certainly represent 
good products. 

The cost of putting a manuscript into print is 
considerable despite the fact that those of us who edit 
and produce The Canadian Field- Naturalist on an 
essentially volunteer basis receive mainly personal 
satisfaction. Expenses for the operation are covered 
through page charges to authors (these contributions 
by no means cover the total cost), subscriptions to The 
Canadian Field-Naturalist, an allotment (40% in 
1977) of the fees paid by members of The Ottawa 
Field-Naturalists' Club, and a grant from the National 
Research Council of Canada. Because several authors 
who had research grant or institutional funds 
available have paid page charges for all published 
pages, not just the obligatory page charges for pages in 
excess of six, our finances are in good shape. 
Nevertheless, in our proposed budget for 1977, we 
included a contingency fund of $2000 to act as a buffer 
for sudden, unanticipated cost increases but this had 
to be removed. Although the committee of the 
National Research Council of Canada that reviewed 
our application for a Scientific Publication Grant was 
sympathetic, it did not wish to contribute to a 
contigency fund in view of the severe competition 
amongst all applicants for the funds available. 
Therefore, the grant we received was considerably 
lower than that requested. For 1978 we are essentially 
operating on a zero-base budget. 

In 1977 The Canadian-Field-Naturalist received 
137 manuscripts for consideration. This number is 
slightly lower than the 147 received in 1976 and the 



peak of 167 in 1975. The four issues of The Canadian 
Field-Naturalist published for 1977 (Volume 91) 
contain 101 scientific papers originally submitted 
from 1974 to 1977. The breakdown according to 
subject matter is as follows: birds, 30; mammals, 31; 
plants, 16; fishes, 10; amphibians and reptiles, 8; 
invertebrates, 4; and others, 2. 

Towards the end of the year Associate Editor for 
Ornithology A. J. Erskine agreed to take on the task 
of dealing directly with authors and referees for all the 
new submissions on birds. 1 anticipate that this will 
lighten considerably my rather heavy work load. 

The April-June issue contained updated details on 
current editorial policy while in the July-September 
issue I commented on and stated the journal policy for 
the reporting of range extensions, this following the 
editorial on the subject by Associate Editor David P. 
Scott. Also noteworthy in the July-September issue 
was the announcement by Associate Editor George H. 
La Roi of our intention to publish in The Canadian 
Field-Naturalist a new series on "The Biological Flora 
of Canada." We hope that the problems involved in 
starting this new series will be worked out and that the 
series will be a welcome addition to the literature. 

Although the high standards of our journal are to a 
certain extent dependent on the way it is edited and 
produced, they must also depend on submissions of 
high quality by authors and on authoritative and 
constructive reviews by referees. The communications 
of appreciation received during the year from 
readers and authors were welcome and personally 
gratifying to us. 

Lorraine C. Smith 
Editor 



Kirkland's Warbler Protected in Ontario 



Ontario recently added Kirkland's Warbler as the 
13th species to be protected under Ontario's En- 
dangered Species Act. A census of the central 
Michigan Jack Pine plains, the only known breeding 
range of the bird, had indicated that only about 450 



birds survive. The bird has been seen in Ontario, 
including a sighting in the summer of 1977. Ontario, 
recognizing a need for cooperation with the Michi- 
gan-based Kirkland's Warbler survival project, has 
now given protection to the species. 



203 



204 



The Canadian Field-Naturalist 



Vol. 92 



1978 Council — The Ottawa Field-Naturalists' Club 

At the Annual Business Meeting of The Ottawa Field-Naturalists' Club on 10 January 1978, the Members of 
Council proposed by the Nominating Committee (including one person nominated by the membership-at-large) 
were elected and are now in office. *New member of Council. 



President: R. A. Foxall 

Vice-President: R. Taylor 

Treasurer: B. Henson 

Recording Secretary: D. R. Laubitz 

Corresponding Secretary: A. Armstrong 



Members of Council 

E. Beaubien 
C. Beddoe* 
W.J. Cody 
J. Diceman 
E. Dickson* 
A. Dugal 
C. Gilliatt* 
C. Gruchy 
P. Hall* 



J. E. Harrison 
V. Hume* 
H. MacKenzie 
J. Murray 
M. Ney 
G. Patenaude 
J. K. Strang 
S. M. Teeple 
E. C. D. Todd 



Request for Participants — International Shorebird Surveys 1978 



A cooperative International Shorebird Survey 
scheme has been organized by the Canadian Wildlife 
Service and the Manomet Bird Observatory since 
1974 to obtain information on shorebird migration 
and to identify and document areas of major 
importance. This scheme has been highly successful, 
with much very valuable information on shorebird 
distribution and migration coming from contributors 
throughout eastern Canada and the USA, the 
Caribbean Islands and Central and South America. 
Information from the scheme will be valuable in 
assessing requirements for the future protection and 
conservation of the birds and their habitat. It is 
planned to make 1978 the fifth and final year of the 



project. Any observer who may be able to participate 
in regular counts of shorebirds during spring and 
autumn migration periods, as well as during the 
winter in shorebird wintering areas, is asked to 
contact one of the undersigned. Occasional counts 
from observers visiting shorebird areas on an irregular 
basis would also be most welcome. For areas in 
Canada: Dr. R. I. G. Morrison, Canadian Wildlife 
Service, 2721 Highway 31, Ottawa, Ontario, Canada 
KIG 3Z7. For areas in USA, Caribbean Islands, 
Central and South America: Brian A. Harrington, 
Manomet Bird Observatory, Manomet, Massa- 
chusetts, USA 02345. 



Request for Information — Shorebird Color-marking 



In 1978 the Canadian Wildlife Service will be 
continuing a large-scale program of banding and 
color-marking shorebirds in James Bay. During the 
past three years, over 30 000 shorebirds have been 
captured, resulting in more than 1200 'bird days' of 
sightings of dyed birds ranging from eastern Canada 
to South America. Much valuable information on 
migration routes and strategies is being obtained and 
observers are again asked to look out for and report 
any color-dyed or color-banded shorebirds that they 
may see. Reports should include details of species 
(with age if possible), place, date, color-marks and, if 



possible, notes on the numbers of other shorebirds 
present. For color-dyed birds, please record the color 
and area of the bird that was dyed. For color bands 
and standard metal leg bands, please record which leg 
the bands were on, whether they were above or below 
the "knee," the colors involved (yellow or light blue), 
and the relative position of the bands if more than one 
was on a leg (e.g., right lower leg, blue over metal, 
etc.). All reports will be acknowledged and should be 
sent to: Dr. R. I. G. Morrison, Canadian Wildlife 
Service, 2721 Highway 31, Ottawa, Ontario, Canada 
K1G3Z7. 



1978 



News and Comment 



205 



Levels for Air Contaminants Adopted 

Maximum tolerable levels have been set for five 
major air contaminants under the Clean Air Act. The 
five contaminants — particulate matter, sulphur 
dioxide, carbon monoxide, oxidants (ozone), and 
nitrogen dioxide — are responsible for 90% of total air 
pollution in Canada. 

Under the Clean Air Act of 1971, three levels for air 
quality were set — desirable, acceptable, and 
tolerable. Desirable is the level where the environ- 
ment generally is not affected; acceptable is the level 
where minimal effects of contaminants are considered 
to be reasonable. When air quality conditions have 
deteriorated to the maximum tolerable level, prompt 
abatement action is necessary by local authorities. 
Surveillance of air quality in Canada over the past 
several years, however, has shown these levels are 
seldom reached. 

Maximum tolerable levels for the five major 
contaminants were developed by a federal-provincial 
committee. The upper range of the five major air 
contaminants for tolerable levels is: particulate 
matter, 400 iJ.g/nv' (24-h average); sulphur dioxide, 
800 Mg/m^ (24-h average); carbon monoxide, 20 
mg/m^ (8-h average); oxidants, 300 Mg/m (1-h 
average); nitrogen dioxide, 300 fj.g/m^ (24-h average) 
and 100 fjLg/m^ (1-h average). 

Desirable and acceptable levels were adopted under 
the Clean Air Act in 1974 for four of the pollutants, 
and in 1975 for nitrogen dioxide. 

These pollutants are produced in a number of ways. 



Particulate matter in solid or liquid form may 
originate with industrial processes as well as other 
human activities, and with nature. Particulates also 
reduce visibility and contribute to property damage 
and soiling. Sulphur dioxide results from industrial 
processes and the combustion of fossil fuels. Oxidants 
are produced in the atmosphere when reactive organic 
substances, chiefly hydrocarbons, are exposed to 
sunlight in the presence of nitrogen oxides. In 
addition to their possible connection with respiratory 
diseases, they also damage plants and materials such 
as rubber and textiles. Nitrogen oxides originate 
principally with high-temperature combustion pro- 
cesses. Carbon monoxide results from some industrial 
processes and from incomplete combustion of 
carbon-containing fuels. It decreases the oxygen- 
carrying capacity of the blood, and at excessive levels 
may impair mental processes. 

National Air Quality Objectives are required to 
provide the following: a uniform yardstick to measure 
air quality in all parts of Canada; a basis for keeping 
the air clean in unpolluted parts of the country; a basis 
for determining priorities for tackling pollution 
problems; an indication of the extent of surveillance 
programs required; and a framework for enforcement 
programs by control agencies. 

The newly-adopted Air Quality Objectives (Maxi- 
mum Tolerable Levels) will be published in Part II of 
the Canada Gazette. 



North American Conference on Common Loon Research and Management 



A conference sponsored by the National Audubon 
Society and hosted by Syracuse University was held 
12-14 August 1977 at the Minnowbrook Conference 
Center, Blue Mountain Lake, New York. Priorities 
determined by the participants included (1) estab- 
lishment of an informal working group to serve as a 
clearinghouse for information on research and 
management efforts, (2) collection of historical loon 
nesting records for assessment of recent range 
contraction or expansion by this species, (3) coordina- 
tion and standardization of breeding surveys and an 
effort to document the current breeding status of the 
loon, particularly in the northeastern USA, and (4) 



expanded research, including increased banding 
efforts and initiation of a winter banding program. 
The working group, consisting of Judith W. 
Mclntyre of Syracuse University, Richard L. Plunkett 
of the National Audubon Society, and Rawson L. 
Wood of the Loon Preservation Committee of the 
Audubon Society of New Hampshire, plans another 
meeting next year. Requests for conference sum- 
maries and other inquiries may be directed to the 
coordinator, Judith W. Mclntyre, Biology Depart- 
ment. Syracuse University, Syracuse, New York 
13210. 



Book Reviews 



Zoology 



Wildlife Management in Europe 

By Anne Innis Dagg. 1977. Otter Press, Waterloo. 324 pp. 
Paper $6.50 + .50 postage. 

Readers of Dagg's 1974 book Canadian Wildlife 
and Man will find the present book familiar. The style 
is similar. The audience is basically the same. The 
message: "To study wildlife management in Europe is 
to glimpse problems of our own future." Dagg finds 
little evidence that North American biologists are 
keeping abreast of current wildlife management 
practices in Europe. This book is meant to remedy 
that. In the Preface Dagg writes, "This book was 
undertaken to bring together current research 
interests of Europe into one work, so that North 
American biologists can find out what European 
biologists are doing, and perhaps be stimulated by 
some of their ideas." 

Dagg's point that North American biologists can 
learn much from their European counterparts is well 
taken. We can. Many of us do. Most of the Canadian 
research ecologists (wildlife and otherwise) with 
whom I am acquainted have regular contacts in 
Europe, primarily in Great Britain, Scandinavia, and 
the Soviet Union. Dagg must be more specific when 
she says there is little evidence that North Americans 
are current on European work. Her criticism is 
justified for some institutions and government 
agencies. The European experience is certainly not 
greatly reflected in North American wildlife legisla- 
tion. But at the individual unofficial level a great many 
biologists (perhaps more so in Canada than in the 
USA) have been exchanging data for years. 

The book may be divided arbitrarily into four 
sections. Section I deals with the main biotypes of 
Europe. Section 2 discusses species not adapting well 
to man-made changes. Section 3 is devoted to current 
European management practices of aquatic mam- 
mals, waterfowl, and non-game birds. Section 4 
compares European game management laws and 
harvesting procedures with those in North America. 

Dagg presents a general account of a wide range of 
management programs and practices from 26 Euro- 
pean countries. Two hundred and forty-four animal 
species are mentioned in the book, and some 
comments on management practices or biology are 
given for approximately 75 of these. With such a large 
number, details are impossible. Dagg recognized this 
("This work makes no attempt to be definitive, since it 
is based on research published only within the last 



decade. Its length precludes discussing any one species 
or country in depth . . ."). I feel, however, that she 
could have used a better judgment in selecting the 
pieces for inclusion. Availability of material should 
not have dictated volume. For example, the largest 
single section (9 pages) is on bird strikes, the hazards 
to aircraft from birds. This compares to 4 pages on 
moose. Much European and Soviet work of interest to 
American wildlife biologists is omitted. For example, 
Scandinavian and Russian ungulate range research is 
not mentioned. Likewise there is no comment on the 
large body of Russian and Scandinavian winter 
ecology work. 

I feel that there should have been some discussion of 
the better-known "wildlife" research institutes of 
Europe. Some coverage of institute programs, and 
institute policies relating to visiting scientists, would 
have been valuable, particularly for North American 
biologists without contacts in Europe at present. 

In spite of what I have said previously, this is a 
valuable book. As Dagg states in the Preface, "we may 
be enlightened not only by examining the approach of 
Europeans to wildlife management, but by consider- 
ing their attitudes to the game itself." Wildlife 
administrators, conservationists, and the general 
reader will benefit from this book. The chapters on 
extinction, pollution, legislation, non-game species, 
conservation, and aesthetics have general appeal. 
Discussions of the history and population develop- 
ment of many species, including introduced species, 
will provide much material for university courses. All 
biologists will develop real enthusiasm for the 679 
fully referenced titles in the bibliography. 

In North America the memory of the pioneer 
moving through the unlimited game-filled wilderness 
dies hard. But the acceptance of 'privilege' over 'right' 
is making some headway among the hunting 
fraternity. Although it seems unlikely that our human 
population density will reach that of Europe, 
pressures of our environment will continue to affect 
wildlife. The European experience can be valuable to 
us. This book will help many North Americans realize 
this. If you are reading this review you should also 
read the book. 

Tom Northcott 

Northland Associates Ltd., P.O. Box 1734, St. John's, New- 
foundland A1C5P5 



1978 



Book Reviews 



207 



The Bluebird. How can you help its fight for survival 



By L. Zeleny. 1976. Indiana University Press, Blooming- 
ton. 170 pp., illus. $7.95. 

When I first bought this book, in the fall of 1976, 1 
was disappointed with it. The sketches were attractive 
but the color plates seemed to lack the brilliant hues of 
our most colorful thrush. 

Now, in January 1978, I have come to like this 
work. Most of what I have learned along my nest-line 
of 500 boxes is confirmed herein. I have never raised 
young bluebirds but the author has, and the story is 
valuable. 

Sialia sialis does not overwinter in my area, so I do 
not know what food to supply to keep them alive in 
cold weather. It appears that the imported starling 
eats all of the soft berries from the shrubs before the 
bluebird has arrived from the northern parts of its 
range. This is a solid reason to shoot starlings or 



otherwise kill them. 

I had 31 townships covered by bluebird nesting 
boxes but I was driven out of 21 townships by 
sparrows, or by sparrows plus vandalism. Another 
reason for naturalists to use guns or some type of 
humane trap or some chemical that repels the foreign 
birds. 

We learn, in the book, how tobacco-curing kilns 
killed two million bluebirds and how diligent citizens 
wrapped steel mesh around the chimneys to prevent 
more deaths. 

Altogether, this is a fine work but I do hope that 
future editions will contain some really sparkling 
color plates. 

L. A. Smith 
481 Vaughan Rd., Apt. 207, Toronto, Ontario M6C 2P6 



The African Buffalo. A study of resource limitation of populations 



By A. R. E. Sinclair. 1977. Wildlife Behavior and Ecology 
Series, University of Chicago Press, Chicago and London. 
355 pp., illus. $20 U.S. 

This first-rate book by Sinclair, who now teaches at 
the University of British Columbia, tells the reader not 
only all he wants to know about the African buffalo, 
but a great deal about the ecology of central East 
Africa as well. The text zeros leisurely in toward its 
main subject via the evolution of various members of 
the Bovini tribe, the ecology of the areas where the 
study took place (primarily Serengeti National Park, 
Lake Manyara Park, and Arusha Park), and the 
resource requirements of the buffalo. The daily 
activity, social behavior, reproduction, and growth of 
the buffalo are then considered in detail before the 
author broadens his scope again to consider the basic 
problem of whether such a herbivorous population 
can regulate its own numbers, and if so, how. Indeed 
this book could serve as a text for students of 
population ecology because of its breadth of vision. 

The modern approach to studying wildlife species, 
via their ecology in the widest sense, is an excellent one 
which contrasts markedly with earlier studies in which 
an enthusiastic observer watched and recorded what 
the members of "his" species were doing for a few 
months or a year, then wrote up his notes with little 
thought for the broad principles that lay behind his 
observations. Sinclair's approach required both time 
(six years of field work) and immense resources. He 



acknowledges financial aid from five different 
sources, and immediate practical help from a variety 
of behaviorists, pathologists, veterinarians, botanists, 
and chemists. His work included radio-telemetry 
studies on buffalo, taking a number of censuses by 
airplane, and even visiting Australia to work on wild 
buffalo there. It was obviously a tremendous under- 
taking. 

It is impossible in a short review to discuss Sinclair's 
work in depth, but a mention of some of his findings 
will give an idea of the range of his research. 
,1. Old buffalo, which chew more slowly than young 
ones, are unable to compensate for the poor grinding 
efficiency of their teeth by increasing the amount or 
rate of chewing. 

2. Buffalo tolerate hot weather to some extent by 
increasing their body temperature diurnally, but the 
increase is less than in some ungulates such as the 
camel. 

3. Herd animals move daily two or three times the 
distance covered by bachelor males, and thereby use 
up 4-7 percent more energy, but herd animals suffer 
less predation. 

4. Lions, the only important predator of buffalo, 
account for only 30 percent of the total number of 
buffalo deaths. 

5. Buffalo are hosts to at least 57 species of endo- 
parasites and 17 species of ectoparasites. 

6. The crude density of buffalo was positively 



208 



The Canadian Field-Naturalist 



Vol. 92 



correlated with rainfall, and hence food supply, which 
indicates that the populations were regulated. 
7. A lack of food (primary factor) leads to under- 
nutrition and impaired immunity to disease in 
buffalo. Diseases may then become pathogenic 
(secondary factor) and cause a host's death. 

The format of this book is good, with the main 
findings of each chapter summarized succinctly. The 
many figures are included in the text, which is as it 
should be, but unfortunately the tables are all grouped 
in an appendix. The black-and-white photos too are 
not included in pertinent places in the text where one 



would like to see them, but clumped in one place. An 
appendix lists the common and scientific names of the 
animals mentioned in the book, but little effort is 
made to take advantage of this feature because both 
names are also usually given in the text itself. A list of 
scientific names of plants is given, but their common 
names are omitted. 



Anne Innis Dagg 



Box 747, Waterloo, Ontario N2J 4C2 



Proceedings of the 1975 Predator Symposium 

Edited by R. L. Phillips and C. Jonkel. 1977. Montana 
Forest and Conservation Experiment Station, University 
of Montana, Missoula. 286 pp. $4.00. 

As part of the 55th Annual Meeting of the 
American Society of Mammalogists, a Predator 
Symposium was held. This text contains 18 of the 19 
papers presented at that symposium, along with one 
other paper that the editors felt was appropriate to the 
topic. 

The papers cover predator-prey relationships, 
predator management, behavior and interspecific 
relationships of predators, and predator biology. 
"Some papers deal with the general biology of 
predators while others discuss the complications of 
predator management in today's society." The papers 
all follow the format of the Journal of Wildlife 
Management and most are worthy of publication 
therein. 

The papers "deal with a wide variety of species, 
ranging from anteaters in central America to wolves in 
Alaska." Some of the predators considered are dogs. 
Mountain Lion, Mink, Fisher, Red Fox, Black Bear, 
Spotted Hyena, Coyote, and Polar Bear. The 
symposium was not dominated by consideration of 
any one predator species at the cost of all others. 

A paper by Gipson and Sealander, The ecological 
relationships of White-Tailed Deer and dogs in 
Arkansas, points out that "dogs appeared to be 
relatively inefficient predators as compared with 
wolves, cougars, and possibly coyotes and coyote 
hybrids." Their study was designed to examine the 
effects of repeated harassment by dogs on deer. 

Eberhardt and Sargeant's paper. Mink predation 
on prairie marshes during the waterfowl breeding 
season, attempted to define the impact Mink can have 



on waterfowl production. In their study area, it 
appears that 78 percent of the vertebrates consumed 
by Mink were birds, with most of these being 
waterfowl. 

Mech's paper. Population trend and winter deer 
consumption in a Minnesota wolf pack, attempts to 
analyze "the numbers, net productivity, winter 
activity, territory size and winter predation rate of a 
wolf pack in the west-central Superior Forest." This 
excellent paper alone is well worth the purchase price 
of the book. 

The papers of this symposium suggest that a general 
shift in wildlife management attitude has taken place. 
Wildlife managers are no longer attempting to 
eradicate predator species; rather they are attempting 
to control predators. This attitude is most clearly seen 
in Pils' paper, A case against Red Fox reduction in 
Wisconsin. 

One of the hardest tasks facing wildlife managers 
today is that of public education. The tradition of 
aversion to predators has been well entrenched in the 
public mind. To the hunting public, predators are seen 
as competitive on the natural resource. To the 
farming-ranching public, predators are seen as a 
capital risk factor which directly reduces their 
operational capital. 

Generally speaking, the text contains an excellent 
collection of papers. It is unfortunate that the 
proceedings release date must follow the symposium 
by approximately two years, a delay period of greater 
than that of most journals. 

Peter Croskery 

Ontario Ministry of Natural Resources, Ignace, Ontario 
POT ITO 



1978 

Environment 



Book Reviews 



209 



The John Dorr Nature Laboratory: Management for ecological values 



By Karen Cathey, Susan Cooley, and Kate Ligare. 1976. 
Yale University School of Forestry and Environmental 
Studies, New Haven, Connecticut. 64 pp., illus. Paper $3. 

John Dorr was an inventor and industrialist who 
had a keen interest in conservation and natural 
history. In 1965 Mrs. Dorr presented 35.2 hectares of 
forestland to the Horace Mann-Barnard School, 
Riverdale, New York for use as an outdoor center for 
young people. This site was named The John Dorr 
Nature Laboratory in honor of her husband. 

This 64-page publication is the work of three 
graduate students from Yale School of Forestry and 
Environmental Studies who surveyed the natural 
resources of a 730-hectare tract of land in north- 
western Connecticut. Special attention was given to 
The John Dorr Nature Laboratory which formed part 
of the tract. 

The purpose of the publication is twofold. First, it 
combines a study of the natural resources of the region 
with a discussion of the general ecological principles 
involved. Second, it describes and assesses the 
educational potential of The John Dorr Nature 
Laboratory. The publication succeeds on both counts. 

It is an attractive book, large (8'/2 ^ 11"), with a 
soft cover, and profusely illustrated with photographs, 
sketches, diagrams, and maps (only 5 of the 64 pages 
are without illustrations). The low-key text is 
excellent. 

Basic ecological concepts (each of the book's seven 



sections are built around a particular concept: 
succession, limiting factors, communities, and so on) 
are presented accurately and clearly, and related to the 
Connecticut study area. It is an excellent treatment of 
the natural resources and management considerations 
of the region. 

Floral and faunal species lists are provided. I was 
pleased to see that scientific as well as common names 
are given. There is also a bibliography of 130 titles 
ranging from local history through wildlife and 
ecology to alternative sources of energy. I was 
particularly encouraged to note this latter. 

The educational potential of the Dorr Laboratory is 
considerable. This is made clear in the book. The 
discussion of present and potential use of the area 
clearly shows that the Laboratory's program is a 
multi-disciplinary one. The whole program is based 
on ecological principles, and on stewardship for the 
environment. It combines traditional concepts of 
ecology with progressive attitudes of alternate 
technology (utilizing solar or wind power). The book, 
and the Dorr Laboratory, can serve as useful models 
to any agency considering establishment of a nature 
center. 

Tom H. Northcott 

Northland Associates Ltd., P.O. Box 1734, St. John's, 
Newfoundland AlC 5P5 



The Ecology of the Seas 

Edited by D. H. Gushing and J. J. Walsh. 1976. 
Philadelphia. 467 pp. $19.50. 



Saunders, 



This book is a collection of essays by some of the 
best known marine ecologists and fisheries scientists 
of our day who were brought together for this task by 
Cushing and Walsh. The keynote of the book is, the 
editors believe, that marine ecology is now well 
enough advanced as a quantified science to develop 
refutable hypotheses, and that hypotheses are needed 
to understand the ecological processes of the sea, as 
well as to define the discipline of marine ecology. 

The text is divided into six sections: The Sea and the 
Organisms, a somewhat descriptive section; The 
Structure of Life in the Sea, in which the authors 
discuss the structure of plankton communities; 
Functions in the Marine Ecosystem, a group of essays 
dealing with various levels of marine production; 
Yield from the Sea, i.e., fish; Evolutionary Con- 



sequences, that is, competition and isolating mechan- 
isms; and Theory, or to use the editors' earlier and 
better terminology, 'hypothesis.' 

There is a logical stepwise progression of develop- 
ment in the book from a very detailed and advanced 
description of the physical and biotic properties of the 
sea to production of populations, stability of 
ecosystems, and a hypothesis which encompasses 
these processes. One of the strongest points of the 
book is its extensive up-to-date bibliography. This 
will be extremely helpful for introducing scientists and 
students to the primary scientific literature dealing 
with the oceans. 

For those interested in an advanced treatment of 
marine plankton ecology and its relation to fisheries, 
this book is excellent. It is, however, too advanced for 
most general readers. The book would make a good 
text for a senior-level university course, especially for 
students interested in quantitative ecology. 



210 



The Canadian Field-Naturalist 



Vol. 92 



To my mind the book has been inappropriately 
titled. It should have been called "The Ecology of 
Pelagic Fisheries Food Chains." To title it "The 
Ecology of the Seas," but never discuss intertidal 
ecosystems (except for a brief mention in the chapter 
by K. H. Mann) or coral reefs, is misleading. These 
two ecosystems are major production centers in the 
world's oceans; the intertidal ecosystem is one of the 
major suppliers of organic carbon to shelf waters and 
is therefore of major importance to pelagic food chains. 
On the other hand, complete chapters are devoted to 
vertical migration and patchiness, which are problems 
specific to plankton studies and to fish growth, a topic 
the editors could have more appropriately touched by 
referring the reader to the many available texts. Also, 
the editors state that 98% of marine organisms are 
benthic but include only one chapter on this subject, 
and that devoted largely to commercially important 
benthic invertebrates. 

There is one last complaint, which depending on the 
reader's interests may be either large or small. The 
book lacks explanations. The authors assume that the 
general reader is more knowledgable than in fact he 
may be, and therefore they omit many of the explana- 
tions which could have been included. For instance, 
the wind El Nino is mentioned three times (the second 



time wrongly paginated in the subject index, the third 
not referenced at all (see page 402)), but the writers 
never digress for even that one sentence to tell an 
uninformed reader what, where, why, and when this 
wind occurs. The fact that it can periodically change 
the entire current structure off the coast of Peru, cause 
a collapse in the anchoveta stocks and the associated 
fishery, are tidbits hidden from the reader. This is 
especially disconcerting because in the last chapter 
this very system is used as one of the data bases for the 
ecosystem hypothesis model. 

Every practising or potential marine ecologist, 
as well as anyone interested in zooplankton, 
should read this book. The ecological principles 
expounded are nicely summarized and put to the 
reader succinctly. Oceanic physics, nutrient cycling, 
primary and secondary production of the pelagic 
zone, and fisheries production are convincingly tied 
together. Within its subject area this book will be a 
major reference text for years to come; unfortunately, 
it cannot be considered a general marine ecology text. 

M. J. Dadswell 



Identification Center, Biological Station, St. Andrews, New 
Brunswick EOG 2X0 



Arctic Journey. Paintings, sketches and reminiscences of a vanishing world 



By Peter Buerschaper. 1977. MacMillan, Toronto. 126 pp., 
ilius. $14.95. 

The purpose of the expedition was to provide an 
artistic record of the animals and birds in our last 
frontier, the high Arctic, within their natural setting as 
seen only by a few hardy explorers, scientists, and 
Inuit. The purpose is well fulfilled, but I feel it is even 
surpassed by the sense of wonder and awe portrayed 
in the accompanying diary of the journey. Some may 
wonder that so much can be seen and accomplished in 
a few short weeks, but those who have had the 
privilege can only envy the ability to describe the ever 
changing variety of the arctic spring in such an 
accurate and yet highly enjoyable manner. 

Buerschaper's prints and sketches provide an 
excellent detail of a representative sampling of the 
variety of life in the high Arctic. It is especially 
intriguing to see the presentation of many smaller 
birds and mammals performing spring behavior 
patterns within the background of their own special 
microhabitats. Often these less noticeable species 
receive less than their due since they are much harder 
to find and more difficult to photograph without 
disturbing them in their natural setting. 

Besides the interesting artwork, Buerschaper's 



diary is recommended reading to any who would or 
have experienced the wonder of the arctic environ- 
ment. His 3-week expedition to Resolute and Bathurst 
is filled with the excitement of a first-time venture into 
the unknown. It vividly portrays the wonder and awe 
of a first experience of spring in the Arctic. It warns 
the novice of the frustrations of weather or delays in 
transportation, but also emphasizes the satisfactions 
that a dedicated naturalist can expect. It illustrates 
how one must accommodate oneself to the differences 
in the way of life at an isolated village such as 
Resolute, or even more lonely arctic research camp, 
but it also shows just how much can be accomplished 
in a short period, if one is willing to work and adapt. It 
should also remind the seasoned veterans of how 
lucky they are to experience so much that has been 
seen by so few. 

This book is readable, enjoyable, and highly 
esthetic. It is packed with both casual observations 
and ecological knowledge. It is recommendable 
reading to any with an interest or desire for faraway 
places. 

Wilson Eedy 

Beak Consultants Limited, Mississauga, Ontario L4V 1L9 



1978 



Book Reviews 



211 



Other 



The Backpacker 

By Albert Saijo. 1977. 101 Productions, San Francisco. 
(Canadian distributor Van Nostrand Reinhold, Toronto.) 
192 pp. Paper $3.50. 

This little book is both an introduction to 
backpacking and a comment on the development of a 
"style" for hiking in the wilderness. Eight chapters 
deal with equipment, food, trip planning, and various 
aspects of the trip itself. 

Saijo's mystical regard for the wilderness becomes 
clear early in the book and his views on various 
aspects of backpacking are evident throughout. 
Unfortunately, these views are sometimes expressed 
at the expense of being objective, which could leave 
the inexperienced backpacker either poorly advised or 
confused. For example, the poncho is presented as a 
versatile and essential item for protection against rain, 
but no mention is made of its disadvantages nor is 
there a discussion of the two-piece rain suit which 
many hikers prefer. Most major items of equipment are 
covered adequately, but tents and stoves receive 
incomplete treatment. A comparison of gas-fueled 
and cartridge stoves fails to mention the poor 
operation of the latter type at low temperatures. 

The author stresses the point that individual 
preference will play a major role in food selection, but 
his sample recipes strongly emphasize seeds, grains, 
and fruits obtainable at health and natural food 
stores. In fact, many backpackers would take issue 
with his statement that "supermarkets have sur- 



prisingly little you'd want to take into wilderness" (p. 
104). Other statements of questionable basis include: 
"There is no reason at all to get hurt in wilderness" (p. 
79), "burn used toilet paper" (p. 176), "note that moss 
grows on the north side of trees" (p. 156), and the 
comment on page 162 that the only animal besides 
ourselves that will attack without provocation is the 
dog, which we've trained to express our hostilities. 

The author's style of writing includes the use of non- 
sentences and there are several cases of omitted 
conjunctions and unusual phraseology, but his 
meaning is usually clear. The book is essentially free of 
proofreading errors. A totally new set of black-and- 
white drawings, which are interspersed throughout 
the book, is the major difference between this and the 
1972 edition. Reorganization and addition of material 
has been done in some chapters. 

If one realizes that The Backpacker contains many 
opinions and reads it with an open mind, then this 
book can be an interesting and useful introduction to 
the subject. At a time when there is such a pro- 
liferation of often expensive and unnecessary back- 
packing equipment, Saijo's advice to travel light 
should be carefully considered. 

David A. Lovejoy 



Biology Department, 
sachusetts 01085 



State College, Westfield, Mas- 



NEW Titles 



Zoology 

t Art anatomy of animals. 1977. By Ernest Thompson Seton. 
Reprint of 19th century edition. Running Press, Phila- 
delphia. 200 pp., illus. Paper $5.95. 

Biology of benthic organisms. 1977. Edited by B. F. 
Keegan and P.O. Ceidigh. Proceedings 11th European 
Symposium on Marine Biology, 5-11 October, 1976, 
Galway, Ireland. Pergamon, Elmsford, New York. 630 pp., 
illus. $50. 

Biology of the Reptilia. Volume 6, morphology, part 
E. 1977. Edited by C. Cans and T. S. Parsons. Academic, 
New York. 505 pp., illus. $38. 



Birds in boreal Canada. 1977. By Anthony J. Erskine. 
Canadian Wildlife Service Report Series, Number 41. 
Supply and Services Canada, Ottawa. 71 pp., illus. Paper $5 
in Canada; $6 elsewhere. 

Birds in peril: a guide to the endangered birds of Canada and 
the United States. 1977. By J. P. F. MacKenzie. McGraw- 
Hill, Toronto. 191 pp. $14.95. 

Birds of prey. 1976. By Michael Evertt. Putnam, New 
York. 128 pp., illus. 

Deer of Nova Scotia. 1977. By D. W. Benson and G. D. 
Dodds. Nova Scotia Department of Lands and Forests, 
Halifax. 92 pp. Free? 



212 



The Canadian Field-Naturalist 



Vol. 92 



Dolphins, whales and porpoises. 1977. By D. J. Coffey. 
Macmillan, New York. 223 pp. $17.95. 

Ecology and behaviour of nocturnal primates. Prosimians of 
equatorial west Africa. 1977. By P. Charles-Dominique. 
Translated by R. D. Martin. Columbia University Press, 
New York, x + 278 pp., illus. $17.50. 

Ecology of marine benthos. 1977. Edited by B. C. Coull. 
Papers from a symposium, Georgetown, South Carolina, 
May 1975. Bell W. Baruch Library in Marine Science, No. 6. 
University of South Carolina Press, Columbia, xx + 468 pp., 
illus. $27.50. 

tFaunal remains from Fort White Earth N.W.Co. (1810- 
1813). 1977. By Isobel Hurlburt. Human History Oc- 
casional Paper No. 1. Provincial Museum of Alberta, 
Edmonton, vii + 107 pp. Paper free. 

Fish remains in archeology and paleoenvironmental studies. 

1977. By R. W. Casteel. Academic, New York. 180 pp. 
$16.80. 

Fresh and salt water fishes of the world. 1976. By E. C. 
Migdalski. Knopf, New York. 316 pp., illus. 

Grasshoppers and locusts. A handbook of general acrid- 
ology. Volume 2, behaviour, ecology, biogeography, popu- 
lation dynamics. 1977. By Boris Uvarov. Centre for 
Overseas Pest Research, London, x + 614 pp., illus. $40. 

A guide to eastern hawk watching. 1976. By D. S. Heintze- 
man. Penn State University Press, University Park. 99 pp. 
Paper $5.95. 

Handbook of birds of Europe, the Middle East and north 
Africa. Volume 1. The birds of the western palearctic. 
1977. Edited by S. Cramp and K. E. L. Simmons. Oxford 
University Press, New York. 732 pp. $55. 

Improving fish and wildlife benefits in range management. 

1977. Edited by J. E. Townsend and R. J. Smith. U.S. 
Department of the Interior, Washington. 118 pp. 

The langurs of Abu. Female and male strategies of 
reproduction. 1977. By S. B. Hardy. Harvard University 
Press, Cambridge, Massachussetts. xx + 362 pp., illus. 
$17.50. 

The Lepidoptera of Norfolk Island. Their biogeography and 
ecology. 1977. By J. D. Holloway. Series Entomologica 
Volume 13. Junk, The Hague, vi + 292 pp., illus. Dfl.85. 

t Middle eocene freshwater fishes from British Columbia. 

1977. By Mark V. H. Wilson. Life Sciences Contribution 
Number 113. Royal Ontario Museum, Toronto. 61 pp., illus. 
Paper $3. 

The origin and early evolution of animals. 1977. By E. D. 

Hanson. Wesleyan University Press, Middletown, Connecti- 
cut. X + 670 pp., illus. $35. 



Primate ecology. Studies of feeding and ranging behavior in 
lemurs monkeys and apes. 1977. Edited by T. H. Clutton- 
Brock. Academic, New York. 631 pp., illus. $41. 

Problems in vertebrate evolution. 1977. Edited by S. M. 
Andrews, R. S. Miles, and H. D. Walker. Papers from 
symposium, London, January 1976. Linnean Society 
Symposium Series, No. 4. Academic, New York, xii + 412 
pp., illus. $36.10. 

Proceedings of Perdix I Hungarian Partridge Workshop, 28 

February to 3 March, 1977, Minot, North Dakota. 
1977. Edited by G. D. Kobriger. North Dakota Game and 
Fish Department, Dickinson. 233 pp. $2.50 + 41c postage. 

Quantitative methods in the study of animal behavior. 1977. 
Edited by B. A. Hazlett. Proceedings of a symposium, 
Chicago, 13 November 1976. Academic, New York. 222 pp., 
illus. $12.50. 

Sea otters and seaweed. 1976. By Patricia Lauber. Garrard, 
Champaign, Illinois. 64 pp., illus. 

A season of birds. 1976. By Dion Henderson. Illustrated by 

Chuck Ripper. Tamarack Press, Madison, Wisconsin. 87 
pp., illus. 

Transactions of the 42nd North American Wildlife and 
Natural Resources Conference, Atlanta, Georgia, 5-9 May 

1977. 1977. Edited by K. Sabol. Wildlife Management 
Institute, Washington. 523 pp., illus. Paper $8.50. 

t Why big fierce animals are rare. An ecologist's perspective. 

1978. By Paul Colinvaux. Princeton University Press, 
Princeton, New Jersey, viii + 256 pp. $9.50. 

Wildlife in the garden. 1977. By R. Genders. Faber and 
Faber, Salem, New Hampshire. 232 pp. $7.95. 

Winter birds of the Carolinas and nearby states. 1977. By 
Michael A. Godfrey. Blair, Winston-Salem, North Carolina, 
xxiv + 136 pp., illus. 

The world Oestridae (Diptera), mammals and continental 
drift. 1977. By N. Papavaro. Junk, The Hague, viii + 240 
pp., illus. Dfl. 75. 

Botany 

Aquatic weeds in south east Asia. 1976. Edited by C. K. 
Varshney and J. Rzoska. Proceedings of a Regional Seminar 
on Noxious Aquatic Vegetation, New Delhi, 12-17 
December 1973. Junk, The Hague. 396 pp., illus. Dfl. 110. 

Better trees for metropolitan landscapes. 1976. Edited by 
E. S. Santamour, H. D. Gerhold, and S. Little. Technical 
Report NE-22. U.S. Forestry Service, Washington. 256 pp. 
Paper $3.25. 

Carex in Saskatchewan. 1977. By John H. Hudson. Bison, 
Saskatoon. 193 pp., illus. Paper $10 + 50c postage. 



1978 



Book Reviews 



213 



tGrassland simulation model. 1978. Edited by George S. 
Innis. Ecological Studies 26. Springer-Verlag, New York, 
xxvi + 298 pp., illus. $22.80. 

* A guide to the literature on the herbaceous vascular flora of 
Ontario. 1977. By James L. Hodgins. Available from 
author, 90 Wolfre Avenue, Toronto. 25 pp. Paper $2. 

Multivariate analysis in vegetation research. 1978. By L. 
Orloci. 2nd edition. Junk, The Hague, viii + 450 pp. Dfl. 100. 

North American forest history: a guide to archives and 
manuscripts in the United States and Canada. 1977. 
Compiled by R. C. Davis. Clio Books, Santa Barbara, 
California, xxi + 376 pp. 

tXhe rare vascular plants of Ontario/Les plantes vasculaires 
rares de I'Ontario. 1977. By George W. Angus and David J. 
White. Syllogeus No. 14. National Museums of Canada, 
Ottawa. 64 pp. English + 67 pp. French. Paper free. 

The world's worst weeds. Distribution and biology. 1977. 
By L. G. Holm, D. L. Plucknett, J. V. Pancho, and J. P. 
Herberger. University Press of Hawaii, Honolulu. 609 pp. 

$35. 

Environment 

Applied ecology: a nontechnical approach. 1976. By Alden 
D. Hinckley. Macmillan, New York, x + 342 pp., illus. $8.75. 

The art of Glen Loates. 1977. By P. Duval. Prentice-Hall, 
Toronto. 189 pp., illus. $35. 

Biogeochemistry of a forested ecosystem. 1977. By G. E. 
Likens. Springer-Verlag, New York. 160 pp. $9.80. 

Biogeography and ecology of southern Africa. 1977. Edited 
by M. J. A. Werger. Junk, The Hague. 2 volume set, 1420 
pp., illus. Dfl. 365. 

Biohazard. 1977. By M. Rogers. Knopf, New York, xiv + 
210 pp. $8.95. 

The camper's guide to Alaska, the Yukon and northern 
British Columbia. 1976. By Raymond Bridge. Scribner, 
New York, vi + 169 pp., illus. 

The chemistry of our environment. 1977. By R. A. Home. 

Wiley-Interscience, New York. 784 pp. $27.50. 

Ecological (biophysical) land classification in urban areas/ 
Classification ecologique (biophysique) du territoire dans les 
regions urbaines. 1977. Edited by E. B. Wilken and G. R. 
Ironside. Ecological Land Classification Series, No. 3. 
Supply and Services Canada, Ottawa, xiv + 167 pp. $4. 

Ecology. The experimental analysis of distribution and 
abundance. 1977. By Charles J. Krebs. 2nd edition. Harper 
and Row (Canadian distributor Fitzhenry and Whiteside, 
Toronto). 704 pp. $16.95. 



Ecosystem modeling in theory and practice: an introduction 
with case histories. 1977. By C. A. S. Hall and J. W. Day, 

Jr. Wiley, New York. 684 pp. $29.95. 

Effects of petroleum on arctic and subarctic marine 
environments and organisms. Volume 2, biological effects. 
1977. Edited by D. C. Malins. Academic, New York. 500 
pp., illus. $14.50. 

Energy and the environment: a risk benefit approach. 1976. 
Edited by H. Ashley, R. L. Rudman, and C. Whipple. 
Pergamon, New York, x + 306 pp. $12.50. 

Energy and the environment. A structural analysis. 1976. 
Edited by A. P. Carter. Brandeis University Press, Hanover, 
New Hampshire, xviii + 262 pp. $12.50. 

Environmental analysis. 1977. Edited by G. W. Ewing. 
Proceedings of a conference, Philadelphia, 15-18 November 

1976. Academic, New York. 344 pp., illus. $18.50. 

Environmental impact assessment in Canada: processes and 
approaches. 1977. Edited by M. Plewes and J. B. R. 
Whitney. Proceedings of a conference, Toronto, February 

1977. Institute for Environmental Studies, University of 
Toronto, Toronto. $5. 

tThe environment of Amchitka Island, Alaska. 1977. 
Edited by M. L. Merritt and R. G. Fuller. U.S. Energy 
Research and Development Administration Publication 
TID-26712. National Technical Information Service, 
Springfield, Virginia, xii + 682 pp., illus. $20 in U.S.. $40 
elsewhere. 

Histoire et nature. 1976. Anonymous. Laboratoire d'Eth- 
nobotanique 8. Musee d'Histoire naturelle, Paris. 88 pp. 
Paper 50F. 

tLore and legends of Long Point. 1977. By Harry Barrett. 
Burns and MacEachern, Toronto. 240 pp., illus. $14.95. 

Our fragile water planet. 1976. By C. L. and A. M. Mantell. 
Plenum, New York. 275 pp. $19.50. 

Patterns of evolution as illustrated by the fossil record. 

1977. Edited by A. Hallam. Elsevier, New York, xiv + 
592 pp., illus. $69.50. 

Public involvement in natural resource planning and 
decision making: a selected bibliography. 1976. Council of 
Planning Librarians, Monticello, Illinois. $1.50. 

The southern Appalachians. A wilderness quest. 1975. By 
C. Ogburn. Morrow Paperback, New York. 245 pp. Paper 
$5.95. 



Sulfur, energy and environment. 1977. By B. 
Elsevier, New York, xii + 448 pp., illus. $39.60. 



Meyer. 



*The wild shores of North America. 1977. By Ann and 
Myron Sutton. Knopf (Canadian distributor Random, 
Toronto). 240 pp., illus. $43. 



1 



214 



The Canadian Field-Naturalist 



Vol. 92 



When values conflict: essays on environmental analysis, 
discourses and decision. 1976. Edited by Laurence H. 
Tribe, Corinne S. Schelling, and John Vass. Ballinger, 
Cambridge, Massachusetts, xv + 178 pp. 

World within a world — Everglades. 1976. By T. Lewin. 
Dodd, Mead, New York. 64 pp., illus. 

Miscellaneous 

Alternate energy strategies: constraints and opportunities. 

1976. By J. Hagel III. Praeger, New York, xii + 185 pp. 

The center of life: a natural history of the cell. 1977. By 
L. L. Cudmore. Quadrangle, New York. 176 pp. $8.95. 



Implementing solar energy technology in Canada: the costs, 
benefits and role of government. 1977. By M. K. Berko- 
witz. Renewable Resources Branch Report EF-77-71. 
Supply and Services Canada, Ottawa. 239 pp. 

Land and land appraisal. 1976. By R. O. Whyte. Junk, The 
Hague, xiv + 376 pp., illus. Dfl. 100. 

The nuclear power debate. Moral, economic, technical and 
political issues. 1977. By D. Myers III. Praeger, New York. 

xiv+ 158 pp. $15. 

♦Photography for the joy of it. 1977. By Freeman 
Patterson. Van Nostrand Reinhold, Toronto. 168 pp., illus. 
Cloth $19.95: paper $9.95. 



♦assigned for review 

tbook received and available for review 



The Ottawa Field-Naturalists' Club 



Minutes of the Ninety-eighth Annual Business Meeting of The Ottawa Field-Naturalists' Club 



The 98th Annual Business Meeting of The Ottawa 
Field-NaturaHsts' Club was held in the auditorium of 
the National Research Council, Sussex Drive, on 31 
January 1977. The President, E. C. D. Todd, called 
the meeting to order at 8:08 p.m., with a quorum of 34 
persons present (the final total was 39). The 
Recording Secretary read the minutes of the 97th 
Annual Meeting, which were approved on motion (by 
R. Taylor, 2nd M. Brigham). 

E. Todd referred to business arising from those 
minutes. The Club's 1975 financial statement, which 
had not been ready for approval at the last Annual 
Meeting, was subsequently received and approved by 
Council, for the Club, and published in The Canadian 
Field- Naturalist, as had been arranged at the 97th 
Annual Business Meeting. As suggested at the last 
Annual Meeting, a meeting featuring a panel 
discussion on the pros and cons of land acquisition by 
naturalists' organizations was organized by George 
Neville, and held on 14 September 1976. At the annual 
meeting of the Canadian Nature Federation, the Club 
assisted by organizing and leading excursions, and by 
helping at the registration of delegates. 

In the absence of the Treasurer, R. Foxall called on 
M. Brigham, the Club's accountant to present the 
1976 financial statement. A few items of expenditure 
were queried, but the accountant pointed out that 
most of the major amounts were relatively fixed costs, 
so that even if the minor categories under discussion 
were eliminated, this would not appreciably influence 
the overall totals. In discussion, G. Neville criticized 
the handling of the 1975 financial statement, but it was 
agreed that that irregularity had no effect on 
acceptance of the 1976 statement, which was 
approved on motion (by W. Cody, 2nd H. Mac- 
Kenzie). 

The Annual Report of Council, to be published in 
The Canadian Field-Naturalist, was introduced by E. 
Todd. He commented on some of the highlights, such 
as the adjustment of the proportion of monies 
allocated to the Club and CF-A'^ after the decrease in 
numbers of non-local members, who had instead 
become subscribers to the journal; difficulties of the 
Conservation Committee in dealing with the many 
issues arising; the co-chairmanship, with the National 
Museum of Natural Sciences, of the Macoun Club, 
and the recent appearance of the 1976 Little Bear, the 
assistance of Club members at the Ottawa Duck Club 
open house, for which a letter of thanks was recently 
received; support of a third winter bird feeder (in 
Lucerne); and approval of new by-laws. The report 
was approved by M. Brigham, 2nd D. McClymont. In 
discussion, C. Gruchy queried the number of 



individual subscribers to CF-N; W. Cody reported 
this to be 277, thus almost equalling the net decrease 
(284) in Club membership. Mention of the publication 
Shrike as a part of the Publications Committee report 
was queried, and on motion (by D. A. Smith, 2nd 
L. C. Smith) this reference was to be put elsewhere in 
the Annual Report of Council. The status of Shrike as 
a Club publication had been debated by Council, but 
it had never been referred to the Publications 
Committee. G. Neville moved (2nd L. C. Smith) that 
'the matter of the 1976 Council's endorsement of the 
publication of Shrike, by permitting the Club's name 
to be attached thereto, be referred back to Council for 
direction to the Publications Committee for a 
recommendation on this matter in the Club's interest'; 
this was approved 15 to 9 (with numerous absten- 
tions). D. Gray queried whether Little Bear, which in 
1976 received financial support from the Club, should 
also be discussed by the Publications Committee. It 
was agreed that this was not called for, as it is a 
publication of the Macoun Club, not OF-NC. G. 
Neville queried the procedures of the Conservation 
Committee, and recommended that it be noted that no 
Club or Council approval should be given to reports 
or briefs of this Committee not previously cleared; the 
question of whether this recommendation is at odds 
with the Club's delegation of responsibility to Council 
and the President, and with Council's delegation to 
the Committee and its Chairman, was left open. 
Approval of the Annual Report of Council, as 
amended, was then given. 

Todd then called on M. Ney, as chairman of the 
Nominating Committee, to present the slate: 

President: Roger Foxall; Vice-President: Roger 
Taylor; Treasurer: Barry Henson*; Recording 
Secretary: Diana Laubitz; Corresponding Secre- 
tary: Sally Armstrong; additional members of 
Council: Elisabeth Beaubien, William Cody, Jane 
Diceman, Albert Dugal, Anthony Erskine, Charles 
Gruchy, Jeffrey Harrison, Hue MacKenzie, Jo 
Anne Murray, Marshall Ney, Gavin Nicholson, 
Gerald Oyen, Gilles Patenaude, Kenneth Strang, 
Stanley Teeple, Ewen Todd (Past-President), Stan 
van Zyll de Jong. 
No additional nominations were received in response 
to an appeal published in Trail & Landscape. 
Following approval of the slate, Todd thanked the 
members of the 1976 Council who were retiring after 
the meeting: David Gray, Diane McClymont, 
Patricia Narraway, Pamela Sims.* 
*As the result of a misunderstanding. Mr. Henson declined 
to act as Treasurer, and Ms. P. Sims was co-opted to that 
office by the Council in February 1977. 



216 



The Canadian Field-Naturalist 



Vol. 92 



The auditors for 1977, G. J. Wasteneys and D. A. 
Potter, were approved on motion (by R. Foxall, 2nd 
H. MacKenzie). 

Todd then called on H. MacKenzie to report for the 
Centennial Steering Group. MacKenzie noted that 
Council had been asked for, and had given direction 
on, planning policies; the Group now had 27 
proposals on hand (compared to 19 a year ago), of 
which only three or four have been eliminated; some 
projects need a long lead time and others very little, 
but all need active leaders; an overall Public Relations 
co-ordinator will also be essential. G. Neville 
suggested polling Club opinion on various topics 
rather than leaving all decisions to Council, and L. C. 
Smith urged a special general meeting on the subject 
after the projects had been chosen; appeals in Trail & 
Landscape or at the Annual Dinner were also 
suggested for enlisting interested persons to work on 
various projects. 

Todd called attention to the public hearings, before 
the Ontario Municipal Board, of the Ottawa-Carleton 
Region official plan, to start 14 February 1977, and to 
continue for several months. Appeals have been 
launched on many points, including a number of the 



designated conservation areas, most of which stem- 
med from recommendations of the Club's committees 
in past years. It is probable that the Club's role will be 
to brief the City of Ottawa and Region officials 
regarding details of natural values in areas that have 
been challenged, rather than directly contesting the 
challenges. Volunteers for any necessary action are 
needed, but the schedule of relevant hearings is still 
uncertain. 

In closing, Todd thanked the membership for the 
opportunity of his two and a half years as President, 
and expressed thanks also to various individuals for 
their efforts, those named being R. Foxall, A. Erskine, 
W. Cody, H. MacKenzie, and C. O'Keefe. 

The incoming President, R. Foxall, thanked Todd 
for his excellent service as President, and expressed 
his own enthusiasm for the planning that will lead up 
to the Club's centennial celebration in 1979. 

Adjournment of the meeting (on motion by G. 
Wasteneys) was at 10:29 p.m. 

In view of the late hour, no entertainment was 
presented following the refreshments. 

A.J. Erskine, Recording Secretary 



Report of Council to The Ottawa Field-Naturalists' Club 



During 1977 there have been meetings and dis- 
cussions between the Club and the Department of 
National Defence on the matter of access to Shirleys 
Bay. We have now received notice of the conditions 
under which we might be granted access; in September 
1977 the Council approved the start of preHminary 
negotiations on a contract. 

Action has also been taken in the matter of a 
"corporate memory," and statements of responsi- 
bilities of the committees, officers, and servants of the 
Club are being drawn up for approval by the Council. 

Preparations for our Centennial continue, and the 
Centennial Steering Committee brought three pro- 
jects before the Council for approval: The Orchids in 
the Ottawa District; an Index to The Transactions of 
The Ottawa Field-Naturalists' Club and The Ottawa 
Naturalist; and a reprint of the Autobiography of 
John Macoun. Other project leaders will be present- 
ing their proposals in the coming months. The June 
meeting of the Club discussed the Centennial, and a 
number of useful ideas and suggestions resulted. A 
major proposal was that a conference should serve as 
a focal activity, with other functions, such as 
exhibitions and competitions, taking place at the same 
time. Regrettably few volunteers have come forward 
to work on or help co-ordinate Centennial projects. 



As a result, some may have to be discarded owing to 
lack of active support. Financing the Centennial will 
be one of the important activities faced by the Council 
in 1978. A volunteer willing to serve as a Ways and 
Means chairman for this purpose is currently being 
sought. (H. MacKenzie) 

Finance Committee. At the 98th Annual Meeting 
Barry Henson was elected Treasurer; however, due to 
a prior commitment on Monday evenings, he would 
have been unable to attend a Council meeting before 
September. He resigned from the post, and Council 
appointed the former Treasurer, Pamela Sims, to a 
third term. The Committee expresses its appreciation 
to Mrs. Sims. Early in 1977 the budget was prepared, 
and adopted by Council. A number of recommenda- 
tions made by the auditors, concerning accounting 
procedures, as adopted. The most significant of 
these was the amalgamation of the seven bank 
accounts into one. One of the auditors, Doug Potter, 
also pointed out that the Club could profitably make 
use of 30- and 60-day term deposits. He volunteered to 
analyze the cash flow and arrange for the transfer of 
funds to these deposits, which he was authorized to 
do. More than $1000 was gained in interest during the 
past financial year, most of it going to The Canadian 
Field-Naturalist. We are grateful to Mr. Potter for his 



1978 



The Ottawa Field-Naturalists' Club 



217 



recommendation and action, and we strongly recom- 
mend the continuance of this investment policy. In 
view of the deficit budget presented to Council, and of 
the current high rate of inflation, it was felt that the 
$2.00 increase in membership fees that had been 
recommended would prove inadequate; a $3.00 
increase was recommended to Council. After some 
debate the fee changes were passed unanimously. 
Doug Potter made yet one more recommendation, to 
change the financial year end to September 30. This is a 
good time to close the books, as it is a slack time in the 
Club's finances, and it avoids the Christmas - New 
Years season, thus relieving the pressure on the 
volunteer help on which the Club is so dependent. 
Council accepted this recommendation unanimously, 
and the 1977 financial statement covers the period 
January 1 to September 30. Pamela Sims expressed 
her desire to resign at the end of the financial year, and 
Council acted upon the recommendation of the 
Finance Committee to re-appoint Barry Henson as 
Treasurer. (R. Taylor) 

The Membership Committee reported that the total 
membership has increased by 35 over 1976. It is with 
regret that the committee announces the death in 
November 1977 of Dr. A. E. Porsild, an Honorary 
member and a former President of the Club. 

(M. Ney) 

The Publications Committee reported that four 
issues of The Canadian Field-Naturalist, volume 90(4) 
and volume 91(1, 2, 3), with a total of 498 pages, have 
been published since the last report. The total number 
of articles and notes published during the period was 
111, comprising 37 papers on birds, 36 on mammals, 14 
on plants, 9 on fishes, 7 on reptiles and amphibians, 2 
on insects, and 5 on other topics. The number of 
manuscripts submitted to the Editor in 1976 was 147; 
64 book reviews were also published. Grants in 
support of the journal were received from the 
National Research Council of Canada ($5000) and the 
Canadian National Sportsmen's Show ($500), for 
which we are grateful. Trail & Landscape appeared in 



five issues totalling 152 pages of articles and 
information of local interest. Shrike, a newsletter for 
bird-watchers in the Ottawa area, became an official 
publication of the Club. Special thanks are due to 
Harry Thomson, who is leaving Trail & Landscape 
after 1 1 years of valuable and dedicated service. 

(S. van Zyll de Jong) 

During 1977 the Excursions and Lectures Commit- 
tee organized 36 excursions, 10 monthly meetings, a 
workshop for excursion leaders, and the annual 
dinner. The field trips were related to birds (21), 
general topics (10), botany (3), mineralogy (1), and 
butterflies (1). The two bus excursions were highly 
successful, and the committee recommends that more 
bus excursions be organized in 1978. Statistics are 
now being kept on all excursions in order to assess the 
entire program, and to learn what factors influence 
the numbers of participants. It is anticipated that 
attendance at the monthly meetings will improve as a 
result of the move from the Activity Centre at the 
National Museum of Natural Sciences to the 
auditorium in the same building. The leadership 
workshop was a very useful exercise; however, it was 
clear that this workshop only scratched the surface, 
and that there is a great deal more to be learned. The 
committee considers a follow-up to this exercise in 
1978 to be mandatory. The speakers at the annual 
dinner were Kay and Larry McKeever, the "owl 
people" from Vineland, Ontario. Their fascinating 
talk, combined with the excellent hot and cold buffet 
at the Talisman Motor Hotel, made a highly 
successful evening. (R. Taylor) 

During 1977 the members of the Conservation 
Committee decided that (1) the major efforts of the 
committee should be concentrated within a 30-mile 
radius of Ottawa, but that exceptions would be made 
in the area beyond this where no other organization 
exists to take action; (2) any statements on policy, 
including briefs, should be approved by elected 
representatives of the Club before they are released; 



Membership of the Ottawa Field-Naturalists' Club. 





Canadian 


Canadian 


Membership 


(local) 


(other) 


Individual 


438 (408) 


342(324) 


Family 


207 (203) 


22 (23) 


Sustaining 


10(9) 


3(2) 


Life 


9(7) 


6(4) 


Honorary 


5(6) 


4(4) 


Totals 


669 (633) 


377 (357) 


Changes 


+36 


+20 


Grand Total 


1163(1088) 





USA 



Foreign 



106 (85) 


2(3) 


nil 


1 (1) 


nil 


109 (89) 


+20 



5(6) 
1(1) 
nil 

2(2) 
nil 

8(9) 
-I 



NOTE: Year 1976 shown in brackets. 



218 



The Canadian Field-Naturalist 



Vol. 92 



(3) participation on non-Club committees that were 
concerned with conservation issues in the Ottawa- 
Hull region was valid; and (4) due to deficiencies in 
knowledge of natural history within the 30-mile radius 
area, expeditions would be held to gather informa- 
tion. The committee has therefore been participating 
in the Ontario Municipal Board hearings into 
conservation areas in the Ottawa-Carleton Region; in 
the Ontario Royal Commission on Power Planning; 
and in Power Planning in Eastern Ontario, organized 
by Ontario Hydro. At least 13 field trips were held to 
visit areas of concern to the committee. Many of these 
have proved useful, since the Ottawa-Carleton Region 
has recently suggested changes to the official plan in 
regard to conservation areas, some of which may be 
deleted. The committee is actively involved in 
considering these proposed changes, and is in close 
contact with the Region about them. The committee is 
also working towards a definition of a conservation 
area and the criteria that determine its value. The 
active participation, and deep concern for conserva- 
tion shown by the members of this committee is 
acknowledged by the Chairman and by the Council. 

(E. Todd) 

The Macoun Field Club Committee reports a very 
successful and productive year for the Club. Gerry 
Fitzgerald (NMNS) and Arnet Sheppard (OFNC) 
have worked very hard, making an interesting year 
for the Junior and Intermediate groups, with weekly 
meetings and monthly field trips about the Ottawa 
region. David Gray continued as supervisor to the 
senior group. They have continued with weekly 
meetings and field trips. Projects have been under- 
taken by each member, according to their interest; for 
example, the report on the Laverendrye canoe trip will 
consist of lists, notes, and descriptions of the area and 



its species. A trip to Point Pelee, sponsored by 
NMNS, was a great success; interest was very high, 
and a large number of members went. The Seniors 
have also been actively helping with the Nature 
Exploration Program in the Gatineau, making cross- 
country skiers more aware of their surroundings and 
of their impact on the environment. Thanks are due to 
the National Museum of Natural Sciences, the group 
chairmen, and particularly the parents who acted as 
chauffeurs for the Club outings. (G. Nicholson) 

The Education and Publicity Committee continued 
to provide trip leaders and speakers for outside 
groups, and judges for the Ottawa Science Fair. An 
exhibit on "Ontario Bats," for the Federation of 
Ontario Naturalists conference in Guelph was built 
and 'manned' by the committee members, and 
received many compliments. The possibility of getting 
occasional feature articles in The Citizen is being 
investigated. With the approval of the Council, 
arrangements are being made to get a Club phone, 
which will be listed under our name in the directory, 
and for the present will be installed in Ellaine 
Dickson's house. (E. Beaubien) 

The Moodie Drive, Davidson Road, and Pink 
Road (Lucerne) bird feeders continue to be supported 
by the Club, along with the new feeders that have been 
set up at the Geomagnetic Laboratory on the 
Anderson Road. And Club badges have been 
available since the spring of 1977, and are proving to 
be quite popular. 

Thanks are extended to all those who helped with 
and contributed to the activities of the Club in 1977. 

Compiled from committee reports 

and Council minutes by 

D. R. Laubitz, Recording Secretary 



Auditor's Report 

To: Members of the Ottawa Field-Naturalists' Club 

We have examined the balance sheet of The Ottawa Field-Naturalists' Club as at September 30, 1977 and the 
related Income Statements for the nine-month period. Our examination included a general review of the 
accounting procedures and such tests of the records and supporting vouchers as considered necessary in the 
circumstances. 

While the bank reconciliation has not been carried out on a month-to-month basis, the bank has been 
reconciled as of September 30, 1977 with the cash in bank per balance sheet. 

In our opinion these financial statements present fairly the financial position of the organization as at 
September 30, 1977 and the result of its operations for the nine-month period in accordance with generally 
accepted accounting principles. 



February 14, 1978 



(Signed) Geoffrey Wasteneys 
James Montgomery 



1978 



The Ottawa Field-Naturalists' Club 



219 



Corrected Financial Statements — February 1, 1978 
The Ottawa Field-Naturalists' Club Balance Sheet 

as at September 30th, 1977 

Assets 

Current 

Cash in Bank & Term Deposits — OFNC 

— CFN 

Bills Receivable 

Accrued Interest Receivable 

Fixed (at cost) 

Furniture, Fixtures & Equipment 

Less Accumulated Depreciation 

Investments and Securities 

Canada Savings Bond 



35,115.10 
3,116.19 
9,290.48 


47,521.77 


529.50 
411.52 


117.98 




10,700.00 




58,339.75 



Liabilities and Equity of Surplus 

Current Liabilities 

Income Received in Advance 

Accounts Payable 

Equity of Surplus 

Balance January 1st, 1977 

Add: Net Income for nine months 



6,916.68 
7,489.00 



38,458.80 

5,475.27 



14,405.68 



43,934.07 
58,339.75 



(Signed) Geoffrey Wasteneys, Auditor 

James Montgomery, Auditor 

Pamela J. Sims, Treasurer 



220 



The Canadian Field-Naturalist Vol. 92 



The Ottawa Field-Naturalists' Club Statement of Profit and Loss — OFNC 

For the nine-month period ended September 30th, 1977 

^^'"'^""^ 3 701 00 

Membership Income onn nn 

Life Membership «';"-^" 

Donations & Grants t\«l<: 

Salelncome 258.65 

Subscriptions T& L 150.00 

Special Activities 323.66 

Interest & Income 

Bank Interest 507.28 

Canada Savings Bonds 557.73 1,065.01 



Less cost of publications 

r&L(Vol. II) 2,147.25 

Circulation ^'l'^^ 

Office & Editorial „^?? 

Honoraria • 

Gross profit on Club operations 



403.18 



6,715.21 



330.00 2,571.16 

4,144.05 



Less operating expenses 

Council Expenses 

Printing & Stationery 53.80 

Committee Expenses — Membership 309.38 

— Excursions & Lectures 266.52 

— Publications ^-^^ 

— Bird Records (net) (28.04) 

— Bird Feeder 248.03 

— Research, Briefs & Conservation 30.55 

— Education 8.07 

— Macoun Club 470.74 

— Orchid Survey 14.41 

Bank Charges & Interest 1 1-'70 

Depreciation Expense 20.82 

Accounting 200.00 

Treasurer's Expense 225.00 2,238.56 

""VfNr I.»05.49 

CTN ;:::;;:::::;::::::::.::; 3,569.78 

Total Net Income 5,475.27 



1978 The Ottawa Field-Naturalists' Club 221 

The Ottawa Field-Naturalists' Club Statement of Profit and Loss — CF-N 
for the nine month period ended September 30th, 1977 

Revenue 

Income 

Memberships 

Subscriptions 

Grants & Donations 

National Research Council of Canada 

Canadian National Sportsmen's Show 

Sale of reprints 

Plates & tab settings 

Extra pages & authors' costs 

Sale of back numbers 

Interest income 

Bank interest 

Canada Savings Bonds 

Less cost of publications 

Volume 91 (Nos. 1, 2 & 3) 

Reprint costs 

Gross profit on operations 

Less operating expenses 

Circulation 

Office assistant 

Postage 

Printing & Stationery 

Editing — Contracts 

— General expenses 

Honoraria 

Net Income 3,569.78 





2,466.87 






8,496.02 




3,750.00 






375.00 


4,125.00 
5,182.00 
1,608.91 
7,380.00 
671.88 




942.52 






836.60 


1,779.12 
19,616.29 


31,709.80 




2,227.26 


21,843.55 
9,866.25 




1,914.78 






1,138.50 






742.18 






236.32 






660.00 






479.69 






1,125.00 


6,296.47 



Instructions to Contributors 



Content 

The Canadian Field-Naturalist is a medium for publica- 
tion of original scientific research papers in all fields of 
natural history that have relevance to Canada. As the journal 
has a flexible publication policy, items not covered in the 
traditional sections (Articles, Notes, Letters, News and 
Comment, and Book Reviews) can be given a special place 
provided they are judged suitable. Naturalists are also 
encouraged to support local natural history publications. 

Manuscripts 

Please submit, in either English or French, three complete 
manuscripts written in the journal style. The research 
reported should be original. It is recommended that authors 
ask qualified persons to appraise the paper before it is 
submitted. Also authors are expected to have complied with 
all pertinent legislation regarding the study, disturbance, or 
collection of animals, plants, or minerals. 

Type the manuscript on standard-size paper, if possible 
use paper with numbered lines, double-space throughout, 
leave generous margins to allow for copy marking, and 
number each page. For Articles, provide a running head, a 
bibliographic strip, an abstract, and a list of key words. 
These items are optional for Notes. Generally words should 
not be abbreviated but use SI symbols for units of measure. 
Underline only words meant to appear in itahcs. The names 
of authors of scientific names should be omitted except in 
taxonomic manuscripts or other papers involving nomen- 
clatural problems. Authors are encouraged to use "proper" 
common names (with initial letters capitalized) as long as 
each species is identified by its scientific name once. 

Although we prefer the names of journals in the Literature 
Cited to be written out in full, these may be abbreviated 
following the Bibliographic Guide For Editors & Authors, 
The American Chemical Society, Washington, D.C. (1974). 
Unpublished reports should not be cited here. Next list the 
captions for figures (numbered in arable numerals and typed 
together on a separate page) and present the tables (each 
titled, numbered consecutively in arable numerals, and 
placed on a separate page). Mark in the margin of the text 
the places for the figures and tables. 



Extensive tabular or other supplementary material not 
essential to the text, typed neatly and headed by the title of 
the paper and the author's name and address, should be 
submitted in duplicate on letter-size paper for the Editor to 
place in the Depository of Unpublished Data, CISTI, 
National Research Council of Canada, Ottawa, Canada 
Kl A 0S2. A notation in the published text should state that 
the material is available, at a nominal charge, from the 
Depository. 

The CBE Style Manual, 3rd edition (1972) published by 
the American Institute of Biological Sciences, is recom- 
mended as a guide to contributors. Webster's New Inter- 
national Dictionary and le Grand Larousse Encyclopedique 
are the authorities for speUing. 

Illustrations — Photographs should have a glossy finish and 
show sharp contrasts. Photographic reproductions of line 
drawings, no larger than a standard page, are preferable to 
large originals. Prepare line drawings with India ink on good 
quality paper and letter (don't type) descriptive matter. Write 
author's name, title of paper, and figure number on the lower 
left corner or on the back of each illustration. 

Special Charges 

Authors must share in the cost of publication by paying 
$45 for each page in excess of six journal pages, plus $5 for 
each illustration (any size up to a full page), and up to $45 per 
page for tables (depending on size). Reproduction of color 
photos is extremely expensive; price quotations may be 
obtained from the Business Manager. When galley proofs 
are sent to authors, the journal will solicit on a voluntary 
basis a commitment, especially if grant or institutional funds 
are available, to pay $45 per page for all published pages. 
Authors may also be charged for their changes in proofs. 

Limited journal funds are available to help offset publica- 
tion charges to authors with minimal financial resources. 
Requests for financial assistance should be made to the 
Editor when the manuscript is submitted. 

Reprints 

An order form for the purchase of reprints will accompany 
the galley proofs sent to the authors. 



Reviewing Policy of The Canadian Field-Naturalist 



Manuscripts submitted to The Canadian Field-Naturalist 
are normally sent for evaluation to an Associate Editor (who 
reviews it himself or asks another qualified person to do so), 
and at least one other reviewer, who is a specialist in the field, 
chosen by the Editor. Authors are encouraged to suggest 
names of suitable referees. Reviewers are asked to give a 
general appraisal of the .manuscript followed by specific 



comments and constructive recommendations. Almost all 
manuscripts accepted for publication have undergone 
revision — sometimes extensive revision and reappraisal. The 
Editor makes the final decision on whether a manuscript is 
acceptable for publication, and in so doing aims to maintain 
the scientific quality and overall high standards of the 
journal. 



TABLE OF CONTENTS (concluded) 

News and Comment 203 

Book Reviews 

Zoology: Wildlife management in Europe — The bluebird. How can you help its fight for survival — 206 

The African Buffalo. A study of resource limitation of populations — Proceedings of the 1975 
Predator Symposium. 

Environment: The John Barr Nature Laboratory: Management for ecological values — The ecology 209 

of the seas — Arctic journey. Paintings, sketches and reminiscences of a vanishing world. 

Other: The backpacker 211 

New Titles: 211 

The Ottawa Field-Naturalists' Club 215 

Mailing date of previous issue 10 April 1978. 



THE CANADIAN FIELD-NATURALIST Volume 92, Number 2 1978 

Articles 

Changes in aspen parkland habitats bordering Alberta sloughs GRAY Merriam 109 

Decline of a Ruffed Grouse population in Manitoba 

Donald H. Rusch, Murray M. Gillespie, and David I. McKay 123 

Distribution and density of Woodchuck burrow systems in relation 

to land-use practices JOHN A. HENDERSON and FREDERICK F. Gilbert 128 

Vascular plant range extensions to the Heart Lake area, District of Mackenzie, 

Northwest Territories WILLIAM J. CODY and Stephen S. Talbot 137 

Range extensions and comments on the vascular flora of the continental 

Northwest Territories WILLIAM J. CODY 144 

Seasonal food habits of the Barn Owl (Tyto alba) on the 
Alaksen National Wildlife area, British Columbia 

Neil K. Dawe, Craig S. Runyan. and Richard McKelvey 151 

Demographic and dietary responses of Great Horned Owls 
during a Snowshoe Hare cycle 

Robert S. Adamcik, Arlen W. Todd, and Lloyd B. Keith 156 

Population size and structure of four sympatric species 

of snakes at Amherstburg, Ontario W. Freedman and P. M. Catling 167 

Distribution of salamanders of the Ambystoma jeffersonianum complex in Ontario 

Wayne F. Weller, W. Gary Sprules and Terry P. Lamarre 174 

Distribution of Giant Cow Parsnip {Heracleum mantegazzianum) in Canada 

J. K. Morton 182 

Notes 

Morphology, diet, and parasitism in Quebec Black Bears Ian Juniper 186 

Late winter bedding practices of Moose in mixed upland cutovers 

John G. McNicol and Frederick F. Gilbert 189 

Spring and summer food habits of an Ermine (Mustela enninea) in the Central Arctic 

David A. Simms 192 

Red Squirrels, Tamiasciurus hudsonicus. in the Salmonier River valley. Newfoundland 

R. Ian Goudie 193 

Flycatching by male Song Sparrows, Melospiza melodia James N.M. Smith 195 

Feeding at a trap-net by Black-crowned Night Herons A.L.A. Middleton 196 

Occurrence of Carex careyana in Canada PETER W. Ball 197 

Wheatears and a Magnolia Warbler in southern Davis Strait Stuart I. Tingley 199 

Records of the European Skipper in Newfoundland BERNARD S. Jackson 200 

First record of the Ancient Murrelet for Alberta 

D. Vaughn Weseloh and Linda McKeane Weseloh 200 

House Sparrows nesting near a Swainson's Hawk nest W. Bruce McGillivray 201 

concluded on inside back cover 



[SSN 0008-3550 



5-c z/i 



MUS. COMf», ZOOU, 

LIBRARY 



The CANADIAN °''' .!™ 



FIELD-NATURALIST 



ARD 



Published by THE OTTAWA FIELD-NATURALISTS' CLUB, Ottawa, Canada 







. '^\ 



'M --..l^aAmMr ■^ ^^P3S-. 



Volume 92, Number 3 



July-September 1978 



The Ottawa Field-Naturalists' Club 

FOUNDED IN 1879 

Patrons 

Their Excellencies the Governor General and Madame Jules Leger 

The objectives of this Club shall be to promote the appreciation, preservation, and conservation of Canada's natural 
heritage; to encourage investigation and publish the results of research in all fields of natural history and to diffuse 
information on these fields as widely as possible; to support and cooperate with organizations engaged in preserving, 
maintaining, or restoring environments of high quality for living things. 

The Members of Council are listed on the inside back cover. 



The Canadian Field-Naturalist 

The Canadian Field-Naturalist is published quarterly by The Ottawa Field-Naturalists' Club with the assistance of a 
contribution from the National Research Council of Canada. Opinions and ideas expressed in this journal are private and do 
not necessarily reflect those of The Ottawa Field-Naturalists' Club or any other agency. 

Editor: Lorraine C. Smith 
Assistant to the Editor: Donald A. Smith Book Review Editor: J. Wilson Eedy 

Associate Editors 

CD. Bird A. J. Erskine David P. Scott 

E. L. Bousfield Charles Jonkel Stephen M. Smith 

Francis R. Cook Charles J. Krebs Robert E. Wrigley 

George H. La Roi 

Copy Editor: Marilyn D. Dadswell Chairman, Publications Committee: J. K. Strang 

Production Manager: Pauline A. Smith Business Manager: W. J. Cody 

Subscriptions and Membership 

Subscription rates for individuals are $10 per calendar year. Libraries and other institutions may subscribe at the rate 
of $20 per year (volume). The Ottawa Field-Naturalists' Club annual membership fee of $ 1 includes a subscription to The 
Canadian Field-Naturalist. Subscriptions, applications for membership, notices of changes of address, and undeliverable 
copies should be mailed to: The Ottawa Field-Naturalists' Club, Box 3264, Postal Station C, Ottawa, Canada KI Y 4J5. 

Second Class Mail Registration No. 0527 — Return Postage Guaranteed. 

Back Numbers 

Most back numbers of this journal and its predecessors. Transactions of The Ottawa Field- Naturalists' Club. 1879- 
1886, and The Ottawa Naturalist, 1887-1919, may be purchased from the Business Manager. 

Business Manager: Mr. W. J. Cody, Box 3264, Postal Station C, Ottawa, Ontario, Canada KlY 4J5 
Book Review Editor: Dr. J. Wilson Eedy, R.R. 1, Moffat, Ontario LOP IJO 

Coordinator, The Biological Flora of Canada: Dr. George H. La Roi, Forestry Sciences Laboratory, 3200 Jefferson Way, 
Corvallis, Oregon, USA 97731 (address valid until August 1979). 

Address manuscripts on birds to the Associate Editor for Ornithology: 

Dr. A. J. Erskine, Canadian Wildlife Service, Box 1590, Sackville, New Brunswick EOA 3C0 

All other material intended for publication should be addressed to the Editor: 

Dr. Lorraine C. Smith, R. R. 3, Stittsville, Ontario, Canada KOA 3G0 

Urgent telephone calls may be made to the Editor's office (613-996-5840), the office of the Assistant to the Editor (613-231- 
4304), or their home on evenings and weekends (613-836-1460), or to the Business Manager's office (613-994-9608). 

Cover: Moose photographed by Bruno Scherrer in Jasper National Park on 14 August 1975. See articles about Moose on 
pages 223 and 252. 



The Canadian Field-Naturalist 



Volume 92, Number 3 



July-September 1978 



Grouping Characteristics of Moose (Alces alces) in 
Riding Mountain National Park, Manitoba 



Richard C. Rounds 

Department of Geography, Brandon University, Brandon, Manitoba R7A 6A9 

Rounds, Richard C. 1978. Grouping characteristics of Moose (Alces alces) in Riding Mountain National Park, Manitoba. 
Canadian Field-Naturalist 92(3): 223-227. 

Grouping characteristics of the Moose (Alces alces) population of Riding Mountain National Park were derived between 
1970 and 1974 from 1955 ground sightings involving 3173 Moose, and three aerial surveys. Total population numbers and 
weather conditions fluctuated considerably, but mean annual group size for all associations remained virtually constant with 
values ranging from 1.6 to 1.7 animals. Nine of the 12 monthly mean group sizes ranged between 1.5 and 1.7 animals. The 
November mean of 2.1 Moose per group was the only statistically significant variation observed. Monthly sex-age 
associations between June and December were analyzed for single male, multiple male, single female, multiple female, female- 
calf, and mixed-sex groups. A November mean of 2. 1 animals per group for all male Moose was the only significant variation 
observed in sex-age associations. Males were generally more gregarious than females, female-calf groups appeared to be the 
most stable aggregations, and the overall pattern of grouping behavior appeared to resemble most closely that for herds with 
approximately equal sex ratios. 

Key Words: Moose, grouping behavior, Manitoba, Riding Mountain National Park. 



Aggregation in Moose {Alces alces) and other 
ungulates has been attributed to a number of 
extrinsic and intrinsic factors. Among extrinsic 
factors commonly postulated are seasonal varia- 
tion in food availability, weather conditions, 
vegetative cover, and predator defense (Peek et 
al. 1974). Intrinsic factors include sex of the 
animal, reproductive activity, care of young, and 
herd composition (Tinbergen 1953; Peek et al. 
1974). 

Data relating to the grouping (aggregation) 
characteristics of the Riding Mountain National 
Park Moose herd for the years 1970 through 
1974 are presented here. A group is defined to 
allow for single animals, and the words 'group,' 
'association,' and 'aggregation' are used inter- 
changeably. Population changes of the herd, a 
description of the study area, and air survey 
methods have already been reported (Rounds 
1977). 



Methods 

From 1970 to 1974, Moose were observed and 
the sightings recorded on field cards. Sex and 
age compositions of observed groups were 
recorded whenever possible and only completely 
identified groups were used in sex and age 
categories. Ground sightings used in this report 
were made by park wardens, professional 
naturalists, and the author. Structured aerial 
surveys in February 1974, December 1974, and 
January 1975 provided comparative informa- 
tion on total mean group size, but were not used 
to discern group composition except for cow- 
calf associations. 

Biases inherent in non-structured field sight- 
ings apply. Available information does not allow 
delimitation of possible sampling variations 
from year to year or month to month. These 
biases should be moderated by the facts that 
most sightings were made while we were 



223 



224 



The Canadian Field-Naturalist 



Vol. 92 



involved in other activities, the number of 
personnel reporting sightings did not change 
significantly, and activities by field staff tended 
to be seasonal and annually repetitive. The more 
important potential biases arose from misiden- 
tification of age or sex of animals. To avoid as 
many problems as possible, I used sightings only 
from the months of June through December for 
sex-age group delimitations because the 
January-May period is anterless for males, and 
consistent adult sex determination was difficult. 

Weather Records 

Systematic weather records are not available 
for Riding Mountain National Park. Short-term 
records for temperature, precipitation, and 
scattered snow-depth records indicate that 
temperatures are slightly cooler (2°C), and 
precipitation 9-17% greater than that at lower- 
lying nearby settlements (Blood 1966; Bailey 
1967). Adjusting precipitation records of nearby 
stations to the percentage increases noted results 
in average expected snowfall of 90-100 cm and 
mean accumulations of 55-60 cm within the 
park. Mean values of maximum snow accumula- 
tions kept at warden stations in various locations 
within the park during the study period are as 
follows: 1969 — 31 cm, 1970 — 31 cm, 1972 — 
38cm, 1973— 36cm, 1974 — 72cm, and 
1975 — 43 cm (unpublished data from park 
files). The winter of 1973-1974 gave the only 
record of snow accumulations above the 
presumed expected value, with most years 
considerably below projected mean values. 

Results 

Grouping Characteristics of Moose 

Because overall mean annual and monthly 
group sizes do not require accurate sex and age 
determinations, the total 1955 sightings and 



3173 Moose reported between 1970 and 1974 
provide the data base. The mean annual group 
size varied only between 1.6 and 1.7 animals 
(Table 1 ). This consistent year-to-year group size 
occurred in spite of the fact that the population 
changed considerably. 

Monthly mean group sizes varied from 1.3 in 
July to 2.1 in November. Nine of the 12 months 
varied only between 1.5 and 1.7 Moose per 
sighting. Analysis of variance indicated that all 
means were not the same, and subsequent Mests 
indicated that the mean group size of 2.1 in 
November was significantly higher than the 
means for other months (P^ 0.10). 

Although group composition was not 
discerned during aerial surveys, the numbers of 
groups and individuals were recorded. During 
February 1974, 254 groups containing 336 
Moose were recorded. One hundred and 
seventy-nine of the observations involved single 
animals (70%) and the mean size for all recorded 
associations was 1.3 Moose. In December 1974, 
146 (59%) of the 246 recorded groups were single 
Moose, and the total count of 385 resulted in a 
mean group size of 1.6. The air survey in 
January 1975 identified 305 groups containing 
478 individual Moose. One half of the groups 
were single Moose, and mean group size was 1 .6. 

Mean group sizes derived from aerial surveys 
approximate those of ground observations. 
Ground observations during February indicate a 
mean value of 1 .6 Moose per group over the five 
years of record. Reports for February 1974, 
however, indicated a mean group size of 1.4 
animals, which is nearly identical with the 1.3 
animals recorded during the air survey. Values 
of 1.6 Moose per group for the December 1974 
and January 1975 surveys correspond with the 
long-term ground observation means for the two 
months. 



Table 1- 


-Moose herd characteristics from ground observations and aerial survey population estimates 




All moose 


Year 


Population No. No. Mean group 
estimate reports reported size 



1970 
1971 
1972 
1973 
1974 

Total/ Mean 



2448 

1896 
1348 



307 
302 
457 
365 
524 

1955 



520 
516 
736 
571 
830 

3173 



1.7 
L7 
1.6 
1.6 
1.6 

1.6 



1978 



ROUNDS: Moose Grouping, Manitoba 



225 



Table 2- 



-Monthly size and composition of adult male and adult female Moose groups, from ground observations, 

1969-1974 





Single 


Mul 


Itiple 


bulls 




All bulls 


Single 


Multiple ( 


:ows 


All cows 




No. 


No. 


Mean 


No. 


No. 


Mean 


No. 


No. 


Mean 


No. No. 


Mean 


Month 


bulls 


groups 


bulls 


group 


groups bulls 


group 


cows 


groups 


cows 


group 


groups cows 


group 


June 


21 


3 


6 


2.0 


24 


27 


1.1 


17 


I 


3 


3.0 


18 20 


1.1 


July 


19 


2 


5 


2.5 


21 


24 


1.1 


25 


5 


11 


2.2 


30 36 


1.2 


Aug. 


23 


5 


10 


2.0 


28 


33 


1.2 


22 


4 


8 


2.0 


26 30 


1.2 


Sept. 


38 


13 


27 


2.1 


51 


65 


1.3 


33 


9 


20 


2.2 


42 53 


1.3 


Oct. 


79 


19 


45 


2.4 


98 


124 


1.3 


64 


12 


27 


2.3 


76 91 


1.2 


Nov. 


21 


28 


84 


3.0 


49 


105 


2.1 


30 


14 


36 


2.6 


44 66 


1.5 


Dec. 


46 


19 


52 


2.7 


65 


98 


1.5 


72 


15 


34 


2.3 


87 106 


1.2 



Adult Male and Adult Female Groups 

Sighting of single adult males occurred in all 
months, but early fall reports were most frequent 
(Table 2). The greatest number of observations 
of lone bulls occurred in October (the breeding 
season), while they constituted the lowest 
percentage of groups in November, after the rut. 
Groups containing more than one adult male are 
also reported in all months with the largest mean 
group size (3.0) reported during November, the 
same month that the mean size for all bull groups 
reached a peak (Table 2). The mean of 2. 1 for all 
bull groups in November is significantly higher 
than the means for other months {P^ 0.10). 

Reports of single adult females were much 
more common than multiple female groups. 
Associations containing more than one adult 
female averaged 2.3 individuals. Single-cow 
sightings were noticeably less frequent during 
the post-breeding period (November), when 
multiple-cow associations reached maximum 
size (Table 2). There are no significant 
differences among the mean group sizes for 
either multiple or all cow groups {P^ 0.10) 



Female-young and Mixed-sex Groups 

Associations containing adult females with 
calves were reported in all months, but sightings 
were rare in June and July when calves were 
small (Table 3). Cows with single calves were 
reported in 89% (N == 169) and cows with two 
calves in 1 1% (N = 20) of the calf-cow groups. 
The mean size for all cow-calf groups does not 
vary significantly throughout the 7-month 
period (Table 3). Unaccompanied calves were 
reported only 19 times in all months during the 
5-yr period. 

Mixed-sex associations were reported in all 
months, but were most common during the rut 
and post-rut period (September-November) 
(Table 3). Bull-cow groups were more common, 
formed a month earlier, and lasted a month 
longer than bull-cow-calf groups. It would 
appear that cows with calves remain with adult 
males only long enough to breed. Mean group 
size for both associations indicates that more 
than one female or male was present with the 
opposite sex on many occasions (the presence of 
two calves with some females may skew the 



Table 



multiple or all cow groups (f^ 0.10). two calves with some lemales may skew the 

3 — Monthly size and composition of female-young and mixed-sex Moose groups, from ground observations, 
1969-1974 





No. 


No. 




























cows 
with 


cows 
with 


All cow-calf groups 


Bull 


-cow groups 


Bull-cow-calf ] 


groups 


All mixed gr 


oups 




















one 


two 


No. 


No. 


Mean 


No. 


No. 


Mean 


No. 


No. 


Mean 


No. 


No. 


Mean 


Month 


calf 


calves 


groups 


animals 


group groups 


animals 


group groups 


animals 


group groups 


animals 


group 


June 


12 


4 


16 


36 


2.3 




_ 


_ 


2 


8 


4.0 


2 


8 


4.0 


July 


8 


1 


9 


19 


2.1 


4 


9 


2.3 


1 


3 


3.0 


5 


12 


2.4 


Aug. 


17 


1 


18 


37 


2.1 


7 


17 


2.4 


2 


9 


4.5 


9 


26 


2.9 


Sept. 


36 


4 


40 


84 


2.1 


28 


68 


2.4 


5 


16 


3.2 


33 


84 


2.6 


Oct. 


35 


4 


39 


82 


2.1 


26 


63 


2.4 


20 


87 


4.4 


46 


150 


3.3 


Nov. 


33 


4 


37 


78 


2.1 


18 


57 


3.2 


5 


22 


4.4 


23 


79 


3.4 


Dec. 


28 


2 


30 


62 


2.1 


13 


36 


2.8 


10 


43 


4.3 


23 


80 


3.4 



226 



The Canadian Field-Naturalist 



Vol. 92 



group size for bull-cow-calf associations). 
Mixed-sex groups are not common during June, 
July, and August when the cows are giving 
birth or suckling new-born calves. There are no 
significant differences (P^ 0.10) among group 
sizes of any of the mixed-sex associations. 

Discussion 

The annual grouping characteristics of all 
Moose were nearly constant (Table 1) despite 
population change and considerable variation in 
winter conditions (Rounds 1976, unpublished 
report, Parks Canada). Aggregations were 
generally smaller in summer and larger in winter, 
but monthly deviations from the total mean of 
1.6 animals were not great except for the 
November post-rut period. Similar trends in 
aggregations have been reported for Moose in 
northeastern Minnesota, Kenai, Alaska, and 
southwestern Montana (Peek et al. 1974). 

Peek et al. (1974) postulated that bull Moose 
are more gregarious than cows, but that herd sex 
ratio has an effect on the aggregation of all 
Moose. In Minnesota and Montana, where sex 
ratios approached equality, the males showed 
greatest tendency to aggregate in fall and early 
winter. In Montana, secondary grouping with 
great variability was noted in May-June. In 
Alaska, with a sex ratio of 20 males per 100 
females, the Kenai Moose population showed 
largest male groups in the summer with 
secondary peaks in November and March. Bull 
Moose in Riding Mountain most closely reflect 
the grouping behavior of herds with nearly equal 
sex ratios, as low summer aggregation, followed 
by marked rut and post-rut increases in group 
size, most closely parallels that of the Minnesota 
and Montana herds. 

Cow Moose without calves do not aggregate 
to any great extent, as mean monthly group sizes 
varied only between 1 . 1 and 1 .3 animals, with the 
exception of a post-rut peak of 1 .5 in November 
(Table 2). This pattern closely parallels that 
observed in Minnesota and Montana (Peek etal. 
1974). Single cows were reported four times 
more frequently than multiple cow groups, 
reflecting the less gregarious nature of females. 

Adult females with calves are aggressive and 
generally avoid groupings with all other Moose 
except males during the rut (Geist 1963). The 
cow-calf group, however, is perhaps the only 



prolonged association characteristic of Moose. 
The monthly variation in cow-calf group size 
from 2.1 to 2.3 (Table 3) illustrates the 
consistency of these groups, and is in accord with 
most other studies (Altmann 1958; de Vos et al. 
1967; Peek et al. 1974). 

Mixed-sex groups were reported in all 
months, but were most numerous during the pre- 
rut, rut, and post-rut periods (September- 
December) (Table 3). Mixed aggregations 
without calves were reported twice as often as 
those with calves. A wide range in mixed-sex 
group size was evident from field observations. 
Aggregations during pre-rut and post-rut 
periods larger than during the rut have been 
reported (Altmann 1959), but evidence from 
Riding Mountain does not support this 
observation. The tendency for cows with calves 
to avoid other aggregations remains consistent 
in that prolonged contact with breeding males is 
not maintained. 

In total, the pattern of mean monthly group 
sizes is most affected by changes in bull and 
mixed-sex aggregations. The post-rut peak in 
association is most closely related to gregari- 
ousness among males and the presence of 
significant numbers of mixed groups. Cow-only 
and cow-calf groups are apparently very stable, 
although cow-only groups were slightly larger in 
November. The summer decrease in mean group 
size is affected by both the solitary nature of 
bulls during this period and the absence of 
mixed-sex groups. 

Weather conditions, vegetative cover, and 
associated seasonal variation in food supply 
have been proposed as factors affecting Moose 
grouping behavior (Edwards and Ritcey 1958; 
Knowlton 1960; Stevens 1970; Peek 1971). In 
mountainous terrain, heavy snows often force 
vertical migration of Moose to low-lying ranges, 
thereby concentrating the population and 
increasing behavioral interaction. Although 
seasonal shifts are evident in Riding Mountain, 
the relief is not sufficient to allow avoidance of 
extreme winter conditions; Moose do not 
concentrate heavily in few areas, and sub- 
sequent effects on grouping behavior are not 
evident. 

Houston (1968) and Geist (1971) suggest that 
dispersal in a Moose population facilitates 
utilization of sparse forage sources. The Moose 



1978 



ROUNDS: Moose Grouping, Manitoba 



227 



of Riding Mountain are widespread within the 
park and occupy nearly every recognized cover 
vegetation. The generally rolling terrain and 
ubiquity of usable forage, therefore, appear to be 
more conducive to dispersal than to aggrega- 
tion. The fact that mean annual group size did 
not vary (Table 1) with changes in both total 
population and widely different winter 
conditions (as measured by snow-depth) 
between 1970 and 1974 suggests that density, 
weather, and food availability have little effect 
on aggregation in this area. 

An advantage to dispersal may be protection 
from predation. The study area has a sizable 
Timber Wolf {Canis lupus) population which 
may affect Moose behavior. Whatever effect 
might occur, however, would be tempered by the 
availability of alternative prey (Carbyn 1974) in 
that Wapiti {Cervus elaphus) and White-tailed 
Deer {Odocoileus virginianus) are common in 
the region. 

Acknowledgments 

I thank R. F. C. Smith for advice and 
reviewing of the manuscript. Research funds 
were provided by the National Research Council 
of Canada, and Parks Canada of the 
Department of Indian and Northern Affairs. 

Literature Cited 

Altmann, M. 1958. Social integration of the moose calf. 

Animal Behavior 6: 155-159. 
Altmann, M. 1959. Group dynamics of Wyoming moose 

during the rutting season. Journal of Mammalogy 

40: 420-424. 
Bailey, R. H. 1967. Report on the forest survey of 

Riding Mountain National Park, 1960. Canadian 

Department of Forestry and Rural Development, 

Forest Management and Research Service Institute, 

Report Number 2. 55 pp. 
Blood, D. A. 1956. Range relationships of elk and cattle 



in Riding Mountain National Park, Manitoba. Canadian 
Wildlife Service, Department of Northern Affairs and 
Natural Resources, Wildlife Management Bulletin, 
Series 1, Number 19. 62 pp. 

Carbyn, L. N. 1974. Wolf predation and behavioral 
interactions with elk and other ungulates in an area of 
high prey density. Canadian Wildlife Service, Depart- 
ment of Environment, Ottawa. 233 pp. 

de Vos, A., P. Brokx, and V. Geist. 1967. A review of 
social behavior of the North American cervids during 
the reproductive period. American Midland Naturalist 
77: 390^17. 

Edwards, R. Y. and R. W. Ritcey. 1958. Reproduction 
in a moose population. Journal of Wildlife Manage- 
ment 22(3): 261-268. 

Geist, V. 1963. On the behavior of the North American 
moose (Alces alces andersoni) in British Columbia. 
Behaviour 20: 377-416. 

Geist, V. 1971. Mountain sheep; a study in behavior 
and evolution. University of Chicago Press. 383 pp. 

Houston, D. B. 1968. The Shiras moose in Jackson 
Hole, Wyoming. Technical Bulletin of the Grand Teton 
Natural History Association 1: 1-110. 

Knowlton, F. F. 1969. Food habits, movements and 
populations of moose in the Gravelly Mountains, 
Montana. Journal of Wildlife Management 24(2): 
162-170. 

Peek, J. M. 1971. Moose habitat selection and relation- 
ships to forest management in northeastern Minnesota. 
Ph.D. thesis, University of Minnesota, Minneapolis, 
Minnesota. 

Peek, J. M., R. E. Le Resche, and D. R. Stevens. 1974. 
Dynamics of moose aggregations in Alaska, Minnesota 
and Montana. Journal of Mammalogy 55(1): 126-137. 

Rounds, R. C. 1977. Population fluctuations of wapiti 
{Cervus elaphus) and moose (Alces alces) in Riding 
Mountain National Park, Manitoba, 1950-1976. 
Canadian Field-Naturalist 91(2): 130-133. 

Stevens, D. R. 1970. Winter ecology of moose in the 
Gallatin Mountains, Montana. Journal of Wildlife 
Management 34: 37^6. 

Tinbergen, N. 1953. Social behavior in animals. Methuen 
and Co. Ltd., London. 



Received 22 November 1977 
Accepted 4 April 1978 



Regional Movements and Mortality of Great Horned 
Owls in Relation to Snowshoe Hare Fluctuations 



Robert S. Adamcik and Lloyd B. Keith 

Department of Wildlife Ecology, University of Wisconsin, Madison, Wisconsin 53706 

Adamcik. R. S. and L. B. Keith. 1978. Regional movements and mortality of Great Horned Owls in relation to Snowshoe 
Hare fluctuations. Canadian Field-Naturalist 92(3): 228-234. 

Banding summaries and recoveries for Great Horned Owls {Bubo virginianus) from wooded regions of the Canadian Prairie 
Provinces were analyzed according to years of population increase and decline. Fifty-three percent of 1 58 individuals banded 
as nestlings were recovered within 25 km of their banding sites; the remaining recoveries were widely distributed over 
distances up to 1305 km. Movements ^25 km were arbitrarily classified as "rjon-dispersal," and those >25 km as "dispersal." 
Accordingly, 64% of recoveries during years of owl population decline were from individuals that had dispersed, but only 28% 
had dispersed during increase years. Mean dispersal distance was also significantly greater during decline years (443 vs. 
323 km). Only 10% of all horned owls recovered during years of population increase had moved > 100 km; 48% moved 
> 100 km during years of decline. Direction of dispersal was largely independent on the population trend. Life-table analyses 
gave mean estimates of age-specific mortality since 1955 of 55, 39, and 22% during first, second, and later years, respectively. 
Mortality rates did not change between years of owl population increase and decline. Fluctuations in Snowshoe Hare (Lepus 
americanus) abundance appear to cause significant increases in horned owl movements, but not in mortality. This contrasts 
with the situation in some European raptors where high mortality allegedly occurs among juveniles during their emigrations 
following dechnes in small-mammal populations. Horned owls cease breeding early in the more extended Snowshoe 
Hare declines, and thus few juveniles are present during hare lows. 

Key Words: Great Horned Owl, Snowshoe Hare, 10-year cycle, population fluctuations, dispersal, mortality. 



Recent studies near Rochester, Alberta, have 
shown that Great Horned Owls (Bubo virginia- 
nus) exhibit strong functional and numerical 
responses to the cyclic fluctuations of Snowshoe 
Hares (Lepus americanus) (Rusch et al. 1972; 
Mclnvaille and Keith 1974; Keith et al. 1977). 
Annual changes in numbers of resident pairs of 
owls on the Rochester study area were found to 
be importantly influenced by ingress and egress 
(Adamcik et al. 1978). We thus decided to 
conduct an analysis of regional banding records 
from the three Canadian Prairie Provinces to 
examine effects of hare fluctuations on horned 
owl movements and mortality over a large 
geographic area. Our general hypothesis was 
that there have been major differences in annual 
movements and post-fledging mortality of Great 
Horned Owls, which were related to the status of 
Snowshoe Hare populations. 

The terms "boreal forest" and "boreal forest 
ecosystem" are applied broadly in the present 
paper to that complex of northern plant commu- 
nities, with or without conifers, in which 
Snowshoe Hares are found. We emphasize this 
point because there are many thousands of 
square miles of forest and woods between the 
Precambrian Shield and the Rocky Mountains 



that are dominated by Trembling Aspen (Popu- 
lus tremuloides). Balsam Poplar (Populus bal- 
samifera), and Paper Birch (Betula papyrifera); 
and it is such deciduous stands that comprise the 
best habitat for Snowshoe Hares in western 
Canada. 

Methods 

Banding Data for Movement and Mortality 
Calculations 

A summary of all Great Horned Owl bandings 
and recoveries for Alberta, Saskatchewan, and 
Manitoba was obtained from the United States 
Fish and Wildlife Service, Office of Migratory 
Bird Management, Laurel, Maryland. Records 
of birds banded outside the Boreal Forest and 
Aspen Parkland zones of these provinces (non- 
habitat for Snowshoe Hares) were deleted. This 
excluded region is largely open farmland and 
Mixed Prairie lying south of 52°10'N (approx- 
imately through the cities of Red Deer and 
Saskatoon), west of 105°20'W, and southwest of 
a diagonal with ends at 51°N, 105°20'W and 
49°N, 103°W. 

The final data set consisted of 158 recoveries of 
birds banded as nestlings since 1950, and 2163 
banding records since 1955 (banding records 



228 



1978 



ADAMCIR and KEITH: GREAT HORNED OWLS AND SnOWSHOE HARES 



229 



before 1955 were not accessible). The total 
recovery rate since 1955 was 7.2%. The majority 
of bandings and recoveries were from Saskatch- 
ewan (1823 and 131), followed by Alberta (333 
and 27) and Manitoba (7 and 0). 

Determination of Population Trends and 
Peak Years 

Numerical trends and peak years among 
Snowshoe Hares and Great Horned Owls were 
estimated from provincial fur returns for Lynx 
(Felis lynx). Our approach was to use cyclic 
peaks in the fur-harvest data as reference points 
for estimating peak hare populations since 1950. 

The hare peaks that occurred at Rochester, 
Alberta, in the falls of 1961 and 1970 (Keith and 
Windberg 1978) were in the first case concurrent 
with, and in the second 1 yr prior to, the peaks in 
province-wide fur returns for Lynx during the 
winters of 1961-62 and 1971-72. That regional 
hare peaks occurred in Alberta during 1970 and 
1971 was also established by an annual question- 
naire, started in 1964, to registered trappers. 
Information summarized earlier by Keith (1963) 
suggested that regional hare populations have 
tended to peak with, or 1 to 2 yr before, peaks in 
Lynx fur returns. We thus assumed in the 
present analysis that hare numbers were highest 
1 yr before Lynx fur peaks. 

Maxima in horned owl populations were also 
estimated from Lynx fur peaks. Actual field data 
on their chronological relationship were limited 
to (1) our observation at Rochester that the owl 
population remained at its maximum for 1 yr 
after the peak in Lynx fur returns (2 yr after the 
hare peak in fall 1970), and (2) Houston's (1971, 
1975) banding records and observations which 
indicated horned owl peaks in Saskatchewan 
during 1960, and 1970 or 1971 — 1 or 2 yr after 
the Lynx fur peaks there. We thus designated the 
cyclic highs of horned owls since 1950 as 
occurring 1 yr after the peaks in Lynx fur returns 
for Alberta, Saskatchewan, and Manitoba 
(Table 1). 

Because these cyclic fluctuations were not 
entirely synchronous over the three provinces, 
the owl banding records for each were first 
segregated according to number of years before 
or after peaks. The data were then pooled to 
create two blocks of years. The first block 
("increasing") consisted of peak years for owls 
plus the 3 yr immediately preceding. According 



Table 1 — Peaks in Great Horned Owl populations, as 

estimated from known peaks in Lynx fur returns. See text for 

discussion of relationship between these peaks 







Peak years' 


Province 


Lynx2 


Horned Owl 


Alberta 


1952 


1953 




1961 


1962 




1971 


1972 


Saskatchewan 


1952 


1953 




1959 


1960 




1969 


1970 


Manitoba 


1952 


1953 




1959 


1960 




1971 


1972 



'Biological year beginning 1 June. 

-As determined from fur returns obtained from annual reports of the 
Alberta Department of Lands and Forests, the Manitoba Depart- 
ment of Mines and Natural Resources, and the Saskatchewan 
Department of Tourism and Renewable Resources. 

to our Rochester studies, all years in this 
grouping should be characterized by 100% 
nesting among resident pairs of horned owls 
(Mclnvaille and Keith 1974; Adamcik et al. 
1978). The second block ("decreasing") com- 
prised the 3 yr immediately post-peak. We 
compared dispersal and mortality between these 
blocks of years. 

Calculation of Recovery Distances 

In data obtained from the banding office, the 
location of each banding and recovery record is 
defined by the 10-min rectangular area of 
latitude and longitude in which the record 
occurs. The coordinates used in coding location 
are those of the rectangle's southeast corner. 
Recovery distance was that distance between the 
banding and recovery coordinates. This ap- 
proach produces an inherent error, since a bird 
could conceivably move diagonally within the 
10-min rectangle in which it was banded (a 
maximum distance of approximately 22 km) 
and still be recorded as having made no 
movement. Conversely, an individual could 
move a short distance into an adjacent rectangle 
and thus be recorded as recovered in its south- 
east corner (a distance of 7 to 22 km). This error 
is quickly reduced as recovery distance increases. 
All movements of ^ 25 km were grouped into a 
single category in our analysis to minimize such 
errors. 



230 



The Canadian Field-Naturalist 



Vol. 92 



0) 

LU 

cc 

LU 

> 

o 
o 

LU 
CC 

U- 

O 

DC 
LU 
CQ 



TOO -I 



80 



60 • 



40 



20 



(53) 




0-25 26-50 5 



75 '76-100 



101-1350 



INTERVALS OF RECOVERY DISTANCE (KM) 

Figure 1. Frequency histogram illustrating the pattern of recovery distances of 158 Great Horned Owls banded as nestlings. 
Figures in parentheses are percentage of total recoveries within the interval. 



Results 

Dispersal 

To gain an overview of horned owl move- 
ments in the north, we first examined the general 
pattern of band recoveries. Of 158 recoveries of 
birds banded as nestlings, 84 (53%) occurred 
within 25 km of the banding site. A frequency 
histogram of recovery distances (Figure 1) 
exhibited a sharp decline after 25 km, with the 
remaining recoveries spread over intervals of up 
to 1305 km. We thus arbitrarily defined all 
movements ^ 25 km as "non-dispersal" and 
those > 25 km as "dispersal." 

The proportion of banded owls recovered at 
distances > 25 km was highest (P < 0.05) within 
the block of years of population decline (64 vs. 
28%). This difference in apparent dispersal 
(Table 2) was also significant when annual 
recoveries within the 3-yr decreasing block were 



segregated and tested individually against years 
of population increase. 

Dispersal distances within each block of years 
were subjected to a log-transformation to ap- 
proximate a normal distribution before testing 
the difference between their means. The mean 
distance at which dispersing owls were recovered 
was greater (P < 0.05) within the decreasing-year 
block (443 km) than during increasing years 
(323 km). The patterns of dispersal were also 
different: recoveries during years of increasing 
population were mainly (90%) within 100 km of 
the banding site, but five of the seven birds that 
exceeded this distance had moved beyond 
700 km. Recoveries during declining years, on 
the other hand, were more continuously distri- 
buted, with only 51% at less than 100 km (Table 

3). 

The assessment of directional tendencies in 



Table 2 — Comparison of dispersal among Great Horned Owls during 4 consecutive years of population increase and 3 
consecutive years of decline. Total band recoveries each year are shown in parentheses. All birds banded as nestlings 

Population increase or decline years 



Mean 



% dispersing in 

years of population increase 25(12) 18(11) 37(19) 

%dispersing in 

years of population decline 58(24) 62(29) 77(13) 



28(32) 



28 
64 



1978 



ADAMCIK and KEITH: GREAT HORNED OWLS AND SNOWSHOE HARES 



23: 



Table 3 — Distribution of recovery distances of Great Horned Owls during 4 yr of population increase and 3 yr of decline. All 

birds banded as nestlings 

Recovery distances (km) 



0-25 



26-99 



100-299 



300-1350 



% of 74 recoveries in 
increase years 

% of 66 recoveries in 
decline years 



72 
36 



15 



7 
30 



dispersal (> 25 km) was complicated by denser 
human populations and hence increased proba- 
bility of band recovery to the south. We 
therefore compared the proportion of recoveries 
which were north and south, and then east and 
west, of banding locations during years of 
population increase vs. decline. These propor- 
tions were not statistically different: 67% of 
recoveries were to the south during increase 
years vs. 69% during decline years; 67% were to 
the east during increase years vs. 76% during 
decline years. We thus concluded that the 
direction of dispersal was largely independent of 
population trend. 

Houston (1978) analyzed 209 returns from his 
own bandings in Saskatchewan. Eighty-seven 
recoveries at 10 to 250 km from banding sites 
showed no apparent directionality, but 35 of 36 
recovered beyond 250 km had moved southeast 
(31 of the 35 during population declines). The 
above analyses and earlier field observations 
(Swenk 1937; Speirs 1939) led Adamcik et al. 
(1978) to speculate that "...dispersal among the 
vast majority of horned owls is essentially 
random in all years, but ... during periods of 
population decline there is a cohort which does 
move well to the south and hence out of the 
Boreal Forest ecosystem. The fact that none of 
Houston's owls which had moved over 250 km 
southeast were recovered during May-August 
suggests that even these long-range dispersers 
probably return north in spring and summer...." 

Mortality 

We used life-table analyses of band returns to 
estimate average annual mortality rates of 
northern horned owls, and also compared rates 
in years of increasing and decreasing population. 
Birds were considered to be entering their second 
year of life on 1 June of the first calendar year 
after banding; only individuals banded as nest- 



lings were utilized in this analysis. 

Band returns could be broadly classified as 
coming from two sources: (1) shot and trapped 
birds, and (2) birds found dead. Although the 
second source is probably not wholly inde- 
pendent of the first, it seems reasonable to 
assume that it more closely approximates a 
sample of natural mortalities. The key piece of 
information provided here by band returns is age 
at death (d v data); to obtain an unbiased estimate 
of age-specific mortality from a composite 
dynamic life table this sample of band returns 
must be representative of age at death for the 
population as a whole. 

Earlier studies on a variety of birds have 
shown that shot and trapped samples tend to 
contain a disproportionate number of young 
individuals (Lack 1943; Hickey 1952; Haukioja 
and Haukioja 1970), and thus yield overesti- 
mates of early mortality when used as a sample 
of the living (Iv data) in a composite Hfe-table 
analysis. This bias, would, of course, not occur, 
or would be minimal, where mortality from 
shooting and trapping constituted all or an 
overwhelming proportion of total mortality, i.e., 
where the data could be considered as dv rather 
than Ix in nature. There is, however, no evidence 
that this was the case among horned owls, since 
reported first-year losses to guns and traps 
amounted to only 1 .6% of bandings compared to 
estimated total first-year mortality of 55% as 
discussed later. Although some shot and trapped 
birds which carried bands were doubtless not 
reported, the difference between the foregoing 
rates is so great that we can safely conclude that 
hunting and trapping accounted for only a small 
fraction of total annual mortality. 

As a result of the above consideration, we 
decided to utilize only recoveries in the "found- 
dead" category as dv data. Recoveries of "shot 



232 



The Canadian Field-Naturalist 



Vol. 92 



Table 4 — Summarized life-table data, and calculated age-specific mortality among Great Horned Owls banded as nestlings in 
forest and parkland regions of Alberta, Saskatchewan, and Manitoba during 1955-1973 





Banded 


Recoveries other 




Recoveries 


from 




Mean 


Age 


owls 


than from 


shootin 


g Calculated 


shooting 


and 


Calculated estimate 


interval 


available 


and trapping 


mortality 


trappmg 


mortality of 


(yr) 


for 
recovery 


(d-v data) 


rate 


(l.v data) 


rate 


mortality 




Number 


Percent 


Number Percent 


rate 


0-1 


2163 


61 


2.82 


0.58 


34 


1.57 


0.52 


0.55 


1-2 


2123 


12 


.57 


0.28 


16 


.75 


.49 


0.39 


2-3 


1845 


7 


.38 \ 




7 


.38 N 


\ 




3^ 


1608 


6 


.37 




2 


.12 






4-5 
5-6 


1279 
981 


2 
I 


.16 
.10 


0.26 


1 
2 


.08 
.20 


0.18 


0.22 


6-7 


669 


1 


.15 




1 


.15 






Older' 




1 


.29 ^ 




1 


.35 ^ 


) 




Totals 


and means 


91 




0.39 


64 




0.44 


0.41 



'The two older recoveries occurred at age intervals 11-12 and 13-14 yr. 



and trapped" birds were analyzed as l.v data with 
the expectation that the resulting estimate of 
first-year mortality would be biased upward, 
and thus higher than that from the analysis of 
"found-dead" recoveries (Table 4). This proved 
not to be the case, suggesting that the "shot and 
trapped" sample did not contain a dispropor- 
tionate number of young individuals, or that 
both samples were similarly biased. Since we 
could not resolve this problem further, the 
results of each analysis are given here. Lacking 
information on annual variation in the proba- 
bility of recovering banded owls, we assumed 
that this fluctuated randomly and that potential 
errors in age-specific mortality estimates were 
thus self-cancelling over the 20-yr span of data. 
Overall mortality since 1955, as estimated 
from 91 "found-dead" recoveries (d.v) corrected 
for incomplete cohorts (Haldane 1955), was 58% 
in the first year of life, 28% in the second, and 26% 
annually thereafter (Table 4). Estimates for the 
same age classes from 64 shot-and-trapped 
recoveries (Iv) were 52, 49, and 18%. In view of 
the similarity of calculated first-year mortality 
rates, and because of small sample sizes, we feel 
that the best estimates of average annual 
mortality among the three age classes are 
probably given by the mean values of 55, 39, and 
22% (Table 4). These are close to the average 
first-, second-, and later-year mortality rates of 
50, 40, and 29% calculated by us from 288 
recoveries of horned owls banded and recovered 
continentally through 1965-66, as summarized 



from Stewart (1969) and Henny (1972). Esti- 
mates of first-year mortality for both Boreal 
Forest and Continental North American horned 
owl populations differed significantly (P < 0.02) 
from average annual mortality among older age 
classes when tested by chi-square using the 
method of Robson and Chapman (1961). 

Recoveries from nestling banding were parti- 
tioned into years of increasing and peak popu- 
lations vs. years of decline. Only recoveries in the 
found-dead category were utilized because of the 
small samples available, and even here the 43 
and 36 recoveries during increase and decline 
years, respectively, were barely adequate for 
mortality estimates (Table 5). Our conclusion of 
no significant difference in mortality between 
these two year groups must therefore be con- 
sidered tentative. Calculated mean annual mor- 
tality of all age classes was 41% during the owl 
population increase and 38% during the decline. 

Discussion 

The large proportion (53%) of recoveries 
within 25 km of banding (nest) sites indicates 
that horned owls in the Boreal Forest of Western 
Canada usually disperse only- short distances. 
This conclusion is consistent with that of 
Stewart (1969) for the species in general. 
Northern horned owl populations have long 
been thought to fluctuate markedly (Speirs 
1939), and our recent 10-yr study at Rochester 
confirmed this (Adamcik et al. 1978). The 
present analysis suggests that movements differ 



1978 



Adamcik and Keith: Great Horned Owls and Snowshoe Hares 



233 



Table 5 — Summarized life-table data, and calculated age-specific mortality among Great Horned Owls banded as nestlings in 

forest and parkland regions of Alberta, Saskatchewan, and Manitoba during 1955-1973. All recoveries are from other than 

shooting and trapping. Estimates of mortality are separated into years of owl population increase and peak vs. decline 





Banded owls 








Banded owls 








Age 


available for 


Recoveries 


Calculated 


available for 


Recoveries 


Calculated 


interval 


recovery during 
years of popu- 


(d.v 


data) 


mortality 
rate 


recovery during 
yrs of popu- 


(d.v 

Number 


data) 
Percent 


mortality 


(yr) 


Number 


Percent 


rate 




lation increase 








lation decline 










and peak 
















0-1 


1508 


32 


2.12 


0.54 


468 


18 


3.85 


0.64 


1-2 


1047 


7 


0.67 1 




972 


5 


0.51 




2-3 


648 


2 


0.31 




1210 


5 


0.41 




3^ 


369 


1 


0.27 




1336 


5 


0.37 




4-5 









0.33 









> 0.22 


5-6 











614 


1 


0.16 




6-7 


173 


1 


0.58 ' 




301 


1 


0.33 




Older' 











233 


1 


0.43 




Totals anc 


means 


43 




0.41 




36 




0.38 



'The single older recovery occurred at age interval 



12 yr 



between increase and decline phases of these 
fluctuations. 

A number of boreal raptors are noted for mass 
movements. The Hawk Owl (Surnia ulula) and 
Great Gray Owl (Strix nebulosa) are examples 
from Europe (Honer 1963; Hagen 1956; Hog- 
land and Lansgren 1968); the Great Horned 
Owl, Snowy Owl (Nyctea scandiaca), and 
Goshawk (Accipiter gent His) are examples from 
North America (Speirs 1939; Gross 1947; Lack 
1954, p. 209). All tend to be restricted feeders, 
especially in winter months, and Lack (1954, p. 
209) felt that real or impending food shortage 
triggered their emigrations. 

The highly specialized feeding of Great Horn- 
ed Owls was seen at Rochester where Snowshoe 
Hares comprised at least 90% of the winter diet 
during 3 successive years of hare decline. In the 
fourth winter, when hares were at their cyclic 
low, they still comprised 50% of the owls' diet 
(Adamcik et al. 1978). 

The periodic mass movements of northern 
horned owls have been attributed to Snowshoe 
Hare declines (Lack 1954, p. 209), and data 
presented in this paper suggest increased egress 
during periods of low and decreasing hare 
density. Only 10% of horned owl movements 
exceeded 100 km during years of population 
growth when hares were abundant; but during 
years of hare scarcity and consequent owl 
population decline, almost 50% moved more 



than 100 km. We have calculated (Adamcik et 
al. 1978) that there was a net egress of horned 
owls annually from the Rochester study area 
during 1972-1975 when hare populations were 
declining and low. Such losses were equivalent 
to between 9 and 62% of the remaining popu- 
lation of territorial birds each year. 

Movements of horned owls were directionally 
similar for a large proportion of the population 
during egress and non-egress years. Thus in- 
creased dispersal appears mainly to be an ampli- 
fication of usual fall movements, as suggested by 
Svardson (1957) for invasions of non-raptorial 
species. 

Great Horned Owl Movements and Mortality 
That mortality probably did not increase in 
declining horned owl populations supports 
Lack's ( 1 954, p. 209) view that emigration occurs 
before overwinter food shortage becomes cri- 
tical. This contrasts with the so called "morta- 
lity outbursts" or "starvation migrations" of 
some European raptors (Honer 1963; Hoglund 
and Lansgren 1968). Emigrating Barn Owls and 
Great Gray Owls, for example, are often found 
emaciated or starved. The microtine prey of 
these raptors undergo mainly 3- to 5-yr cycles of 
abundance, and support raptor reproduction for 
1 or perhaps 2 yr. The usual rapid decline of this 
prey base affects largely inexperienced juveniles 
which allegedly starve while wandering in search 



234 



The Canadian Field-Naturalist 



Vol. 92 



of food (Honer 1963). The decline among 
Snowshoe Hare populations, on the other hand, 
may take 4 to 5 yr. Breeding activity among 
horned owls stops early in the decline ( Adamcik 
et al., 1978), and hence there are fewer 
juveniles, and fewer individuals in gen- 
eral, to compete for a diminishing food source. 

Acknowledgments 

Financial support for this study was provided 
by the University of Wisconsin, College of 
Agricultural and Life Sciences; the Research 
Council of Alberta; the Canadian Wildlife 
Service; the National Science Foundation 
(Grant GB- 12631); and the Green Tree Garden 
Club, Milwaukee, Wisconsin. We are greatly 
indebted to the Canadian banders, especially C. 
Stuart Houston, for the generous use of their 
data. 

Literature Cited 

Adamcik, R.S., A. W. Todd, and L. B. Keith. 1978. 

Demographic and dietary responses of Great Horned 

Owls during a Snowshoe Hare fluctuation. Canadian 

Field-Naturalist 92(2): 156-166. 
Gross, A. O. 1947. Cyclic invasions of the Snowy Owl and 

the migration of 1945-1946. Auk 64(4): 584-601. 
Hagen, Y. 1956. The irruption of Hawk-owls {Surnia ulula 

(L.)) in Fennoscandia 1950-51. Opuscula Series Zoologica 

Number 24. 22 pp. 
Haldane, J. B. S. 1955. The calculation of mortality rates 

from ringing data. Proceedings of the 11th International 

Ornithological Congress, pp. 454-458. 
Haukioja, E. and M. Haukioja. 1970. Mortality rates of 

Finnish and Swedish Goshawks (Accipiter gentilis). 

Finnish Game Research, Number 31: 13-20. 
Henny, C. J. 1972. An analysis of the population dynamics 

of selected avian species. United States Fish and Wildlife 

Service, Wildlife Research Report 1. 99 pp. 
Hickey,J. J. 1952. Survival studies of banded birds. United 

States Fish and Wildlife Service Special Scientific Report, 

Wildlife Number 15. 
Hoglund, N. H. and E. Lansgren. 1968. The Great Gray 

Owl and its prey in Sweden. Viltrevy 5(7): 363-421. 
Honer, M. R. 1963. Observations on the Barn Owl ^7^)70 



alba guttata) in the Netherlands in relation to its ecology 
and population fluctuations. Ardea 51(214): 158-195. 

Houston, C. S. 1971. Brood size of the Great Horned Owl 
in Saskatchewan. Bird Banding 42(4): 103-105. 

Houston, C. S. 1975. Reproductive performance of Great 
Horned Owls in Saskatchewan. Bird Banding 46(4): 
302-304. 

Houston, C. S. 1978. Recoveries of Saskatchewan banded 
Great Horned Owls. Canadian Field-Naturalist 92(1): 
61-66. 

Keith, L. B. 1963. Wildlife's ten-year cycle. University of 
Wisconsin Press, Madison. 201 pp. 

Keith, L. B., A. W. Todd, C. J. Brand, R. S. Adamcik, and 
D. H. Rusch. 1977. An analysis of predation during a 
cyclic fluctuation of snowshoe hares. Transactions of the 
13th International Congress of Game Biologists, Atlanta, 
Georgia, pp. 151-175. 

Keith, L. B. and L. A. Windberg. 1978. A demographic 
analysis of the snowshoe hare cycle. Wildlife M onographs 
Number 58. 70 pp. 

Lack, D. 1943. The age of some more British birds. British 
Birds 36(11): 214-221. 

Lack, D. 1954. The natural regulation of animal numbers. 
Clarendon Press, Oxford. 343 pp. 

Mclnvaille, W. B. and L. B. Keith. 1974. Predator-prey 
relations and breeding biology of the Great Horned Owl 
and Red-tailed Hawk in central Alberta. Canadian Field- 
Naturalist 88(1): 1-20. 

Robson, D. S. and D. G. Chapman. 1961. Catch curves 
and mortality rates. Transactions of the American 
Fisheries Society 90(2): 181-189. 

Rusch, D. H., E. C. Meslow, P. H. Doerr, and L. B. 
Keith. 1972. Response of Great Horned Ow! popula- 
tion to changing prey densities. Journal of Wildlife 
Management 36(2): 282-296. 

Speirs, J. M. 1939. Fluctuations in numbers of birds in the 
Toronto region. Auk 56(4): 411^19. 

Stewart, P. A. 1969. Movements, population fluctuations, 
and mortality among Great Horned Owls. Wilson Bulletin 
81(2): 155-162. 

Svardson, G. 1957. The "invasion" type of bird migration. 
British Birds 50(8): 314-343. 

Swenk, M. H. 1937. A study of the distribution and 
migration of the Great Horned Owls in the Missouri 
Valley region. Nebraska Bird Review 5: 79-105. 

Received 17 February 1977 (subsequently withdrawn) 
Resubmitted 11 October 1977 
Accepted 21 February 1978 



Alaskan Distribution of the Beluga Whale, 
Delphinapterus leucas 

Craig S. Harrison' and John D. Hall2 

U.S. Fish and Wildlife Service, 800 A Street, Suite 110, Anchorage, Alaska 99501 

'Present address: Hawaiian Islands National Wildlife Refuge, 300 Ala Moana Blvd., Honolulu, Hawaii 96850 
^Present address: U.S. Fish and Wildlife Service, 2800 Cottage Way, Sacramento, California 95825 

Harrison, C. S. and J. D. Hall. 1978. Alaskan distribution of the Beluga Whale, Delphinapterus leucas. Canadian Field- 
Naturalist 92(3); 235-241. 

Results of observations of Beluga Whales from 80 000 kmof aerial survey trackline in Alaska indicate an apparent absence of 
this species in many coastal and most offshore waters. Important populations are located in the Gulf of Alaska, especially the 
Cook Inlet, northern Bristol Bay, Norton Sound, and a northern migratory one which winters in the Bering Sea and summers 
in the eastern Beaufort Sea. Beluga occur regularly in deep water offshore during summer in the Beaufort Sea and can occur 
offshore elsewhere, but are predominantly coastal in the Bering Sea and the Gulf of Alaska. We suspect that there are no 
major populations of this species unreported in Alaskan waters. 

Key Words: Beluga Whale. Delphinapterus leucas. White Whale, Odontoceti, Odontidae, Alaskan cetacea, aerial survey, 
marine mammal. 



Beluga Whales {Delphinapterus leucas) dirt 
distributed throughout the arctic and subarctic 
regions of North America, Europe, and Asia. 
Vladykov (1944) prepared a chart which shows 
that nearly all major concentrations occur in 
shallow bays or estuaries of large rivers north of 
40°N. They can inhabit ice but are limited by an 
inability to make breathing holes in any but the 
thinnest ice (Fay 1974). Papers describing the 
recent status of this species have been published 
for the USSR (Kleinenberg et al. 1964), 
Northern Europe (Nazarenko 1965), and North 
America with emphasis on Canada (Sergeant 
and Brodie 1975). Published work on the 
distribution of Beluga in Alaska have been 
limited to incidental observations and general 
comments (for example, Bailey and Hendee 
1926; Johnson et al. 1966: Fay 1974). This paper 
reports the results of Beluga Whale observa- 
tions from a systematic, Alaska-wide aerial 
survey program including observations from 
both winter and summer months. 

Methods 

Aerial surveys designed to establish the 
seasonal distribution and abundance of marine 
mammals and birds were flown periodically over 
Alaskan coastal and outer continental-shelf 



waters and ice from 1975 to 1977 and totalled 
approximately 80 000 km of trackline. Survey air- 
craft were a modified Grumann turbo-goose 
with improved forward and lateral visibihty, and 
a Lockheed Neptune P2V with a bow plexiglass 
observation bubble. These were flown on 
surveys at an altitude of 30 m and a groundspeed 
of 200 km/h. The aircraft were equipped with a 
Global VLF Navigation System (Karant 1976), 
which utilizes the very low-frequency radio band 
and provides a continuous readout of longitude 
and latitude. Two biologists acted as observers, 
one for each side of the airplane, and a third 
utilized a cassette recorder to record periodic 
geographical positions and observations of 
marine mammals and birds. Approximately 
every 30 min the biologists switched seating 
arrangements to combat observer fatigue 
and to allow one of the three to ease his 
eyestrain by diverting his attention to the 
Global VLF. A 100-m transect width was used 
for birds, but all Beluga were recorded, regard- 
less of distance from the aircraft. Supplementary 
data recorded for all surveys were sea state, 
wind, ceiling, ice conditions, and presence of 
calves. Except for portions of northern Cook 
Inlet, the waters surveyed were clear and free 
from turbidity. 



235 



236 



The Canadian Field-Naturalist 



Vol. 92 




Figure 1. Aerial survey tracklines, November-April 1975-1977. 



Results and Discussion 

Figures 1 and 3 show aerial tracklines flown 
during the winter (November-April) and 
summer (May-October) months, respectively. 
Figures 2 and 4 depict Beluga sightings for 
corresponding time periods. Most trackhnes in 
Figures 1 and 3 were covered more than once 
during each 6-mo period: consequently these 
illustrations portray minimum survey range and 
intensity for each half-year. Specific months 
during which surveys were conducted are 
discussed below. Table 1 lists chronologically all 
Beluga sightings for these surveys and includes 
relevant environmental data. We observed 99 
animals on 29 occasions for a mean 3.5 
animals/ observation. In no instance did we 
encounter large groups of hundreds or 
thousands such as those reported in Hudson Bay 



or the Mackenzie Delta, Canada (Sergeant and 
Brodie 1975). Our relatively low mean herd size 
is probably a result of the fact that we may not 
have censused prime migratory routes during 
migration, nor did we survey calving grounds. 
Further, Beluga apparently are not as numerous 
in Alaska as in Canada (Sergeant and Hoek 
1974). Numbers of observed Beluga are 
minimum estimates since Cetacea spend 
considerable time at depths which do not allow 
visual detection: nevertheless patterns of 
geographical and habitat usage emerge from 
these surveys. 

Western Beaufort Sea 

Surveys in this region were conducted during 
July and August and the region contained 
6000 km of trackline. Beluga pass through these 



1978 



Harrison and Hall: Beluga Whale Distribution, Alaska 



237 



Beaufort Sea 




Bering Sea 



Gulf of Alaska 



.•^^^- 



168 164° 160 156° 152° 148* 

Figure 2. Beluga Whale sightings, November-April 1975-1977. 



waters in migration from the Bering Sea each 
spring en route to feeding grounds near Banks 
Island and calving grounds in the Mackenzie 
Delta (Sergeant and Hoek 1974). They arrive in 
Canadian waters between May and July(Fraker 
1977) and have been recorded at Point Barrow in 
early May (McVay 1973). We had two sightings 
each month in July and August for a total of 35 
animals. All sightings occurred approximately 
100 km offshore, in water depths of 1800 m, and 
in polynya. Distance offshore and water depths of 
Beluga in the Beaufort Sea contrast sharply with 
sightings from the remainder of Alaska in which 
Beluga are found a mean 1 5 km offshore and at a 
mean water depth of 26 m. Therefore our data 
indicate that summer Beluga in the western 
Beaufort Sea are found in offshore leads in 
contrast to the more general situation in which 



Alaskan Beluga utilize estuaries, shallow coastal 
bays, and sounds. The cow and calf (calf 40% 
length of adult) that were sighted in late August 
may indicate an early movement away from 
calving grounds in the Mackenzie Delta and 
possible offshore nursing for young-of-the-year. 

Chukchi Sea 

Surveys of 7000 km of trackline in the 
Chukchi Sea were completed in June, August, 
and October. Beluga have been observed in the 
Bering Strait area during February and March 
(Kleinenberg et al. 1964) and northward 
migration has been documented at Point Hope 
in April (Johnson et al. 1966). Animals have 
been sighted in an estuary north of Cape 
Lisburne in June (Childs 1969) and southward 
migration has been noted at Point Barrow in 



238 



The Canadian Field-Naturalist 



Vol. 92 




164" 160° 156° 152° 148" 

Figure 3. Aerial survey tracklines, May-October 1975-1977. 



October (Bailey and Hendee 1926). Recently, 
Beluga have been sighted in Eschscholtz Bay, 
southeastern Kotzebue Sound (Lloyd Lowry, 
personal communication). Our only sighting in 
this area was a moribund animal seen near 
Kotzebue in August. The relative lack of 
sightings in the western Beaufort and Chukchi 
Seas at a time when they are abundant in the 
eastern Beaufort Sea (Sergeant and Hoek 1974) 
suggests that most of the northern Alaska 
Beluga population spends the summer in 
Canadian waters and that few remain in offshore 
Alaskan waters, especially the Chukchi Sea. 

Bering Sea 

Surveys in the northern Bering Sea have been 
conducted in June, August, and October. 
Surveys in the southern Bering Sea have been 



conducted in February, March, April, June, 
August, and October. A total of 28 000 km of 
trackline was flown. We have no data on the 
distribution of Beluga in the northern Bering Sea 
during winter, and work needs to be done to 
delineate the winter distribution of the eastern 
Beaufort Sea population along the ice frontal 
zone in the northern Bering and southern 
Chukchi Seas. We do have several sightings 
from summer and fall indicating the presence of 
animals in Norton Sound near the mouth of the 
Yukon River. Summer sightings in the southern 
Bering Sea include observations in Bristol Bay 
and offshore in the vicinity of the Pribilof 
Islands. The latter substantiates the statement 
that Beluga "cannot be considered only as a 
coastal animal, as it also occurs in the open sea" 
(Kleinenberg et al. 1964). The lack of summer 



1978 



Harrison and Hall: Beluga Whale Distribution, Alaska 



239 




Bering Sea 



.^^ 



Aleutian I. 



164° 160' 156* 152' 148 144* 

Figure 4. Beluga Whale sightings, May-October 1975-1977. 



sightings in the Kvichak River area, a known 
foraging location (Fish and Vania 1971) is 
attributed to the probability that Beluga were 
located in rivers and river mouths, a habitat 
which we did not survey. Sightings in Bristol Bay 
during the winter months were more numerous 
and are clustered in the northern portion of the 
bay. R. E. Gill (personal communication) has 
been studying bird and mammal populations 
year-round during 1976-1977 in Moller Bay 
using aerial and small-boat survey techniques. 
He has never observed Beluga in his study area. 

Gulf of Alaska 

Approximately 40 000 km of surveys have 
been completed in the Gulf of Alaska during the 
months of January, March, April, May, June, 
July, August, and October. Most sightings 



occurred in the Cook Inlet, especially in the 
vicinity of Tuxedni Bay. The Gulf of Alaska 
population has been considered to be. 
geographically isolated and therefore genetically 
distinct from the Bering Sea population 
(Sergeant and Brodie 1969), and we have no 
evidence to the contrary after fairly intensive 
surveys south of the Alaska Peninsula extending 
from Kodiak Island west to the Aleutian Islands. 
Similarly Murie (1959) and others observed no 
Beluga in this area. The range of this population, 
however, does extend outside of Cook Inlet. We 
have sightings of Beluga in March and July near 
Kodiak Island and another near the entrance of 
Prince William Sound in March. Recently a 
group of 21 animals was sighted during late May 
in Yakutat Bay (Calkins and Pitcher 1977). 
Historically, Beluga have been observed as far 



240 



The Canadian Field-Naturalist 



Vol. 92 



Table 1— Aerial survey sightings of Beluga Whales, Delphinapterus leucas, 1975-1977 













Distance 


Bottom 












to land 


depth 


Date 


Locatior 


1 


Number 


Notes' 


(km) 


(m) 


20 June 1975 


63°26'N 


I64°00'W 


I 




22 


5 


2 July 1975 


72°06'N I54°00'W 


9 


polynya 


100 


1800 


2 July 1975 


72°05'N 


I54°00'W 


23 


polynya; calves 
present 


100 


1800 


16 July 1975 


58°00'N 


154°17'W 


2 




9 


260 


7 October 1975 


60°25'N 


I52°00'W 


I 




1 


5 


7 October 1975 


60°30'N 


152°00'W 


3 




2 


18 


28 February 1976 


58°18'N 


162°00'W 


6 


polynya 


31 


40 


29 March 1976 


59°57'N 


147°22'W 


1 




2 


18 


18 August 1976 


71°45'N 


151°47'W 


2 


polynya 


102 


1800 


18 August 1976 


71°45'N 


151°40'W 


2 


polynya: cow-calf 


110 


1800 


22 August 1976 


66°53'N 


162°36'W 


I 


moribund 


beach 


beach 


26 August 1976 


64°00'N 


164°08'W 


1 




56 


16 


26 August 1976 


64°00'N 


I63°08'W 


1 




19 


16 


26 August 1976 


64°00'N 


163°06'W 


2 




19 


16 


7 October 1976 


64°25'N 


161°22'W 


1 




1 


5 


11 October 1976 


56°28'N 


167°00'W 


2 




152 


110 


15 October 1976 


58°14'N 


157°32'W 


1 




3 


2 


7 March 1977 


60°19'N 


151°57'W 


1 




4 


18 


7 March 1977 


60°08'N 


152°38'W 


3 




1 


10 


8 March 1977 


58°00'N 


152°52'W 


1 




1 


11 


21 March 1977 


58°irN 


157°30'W 


3 




1 


5 


13 April 1977 


6I°03'N 


150°19'W 


I 




3 


18 


13 April 1977 


60°12'N 


152°35'W 


. 1 


calf 


1 


2 


14 April 1977 


60°58'N 


150°04'W 


1 




2 


8 


25 April 1977 


58°40'N 


I58°00'W 


2 




1 


4 


25 April 1977 


58°38'N 


157°56'W 


3 




4 


5 


25 April 1977 


58°40'N 


157°12'W 


4 




8 


5 


26 April 1977 


58°45'N 


158°30'W 


1 




8 


12 


17 June 1977 


60°37'N 


151°28'W 


20 




12 


18 



'Adults and open water except as noted. 



south as the Washington coast (Scheffer and 
Shpp 1948) and bones have been found in 
middens on Kodiak Island (Kellogg 1936). 

Acknowledgments 

Observers on aerial surveys have included 
E. P. Bailey, J. C. Bartonek, K. Briggs, D. R. 
Cline, R. E. Gill, C. M. Handel, S. A. Hatch, 
G. L. Hunt, A. L. Sowls, and R. S. Timson. This 
study was supported by the Bureau of Land 
Management and the National Ocean and 
Atmospheric Administration as part of the 
Outer Continental Shelf Environmental 
Assessment Program. 

Literature Cited 

Bailey, A. M. and R. W. Hendee. 1926. Notes on the 
mammals of northwestern Alaska. Journal of Mam- 
malogy 7(1): 9-28. 



Calkins, D. G. and K. W. Pitcher. 1977. Unusual sight- 
ings of marine mammals in the Gulf of Alaska. 
Abstract, Proceedings of the Second Conference on 
the Biology of Marine Mammals, San Diego, Cali- 
fornia. 

Childs, H. E., Jr. 1969. Birds and mammals of the 
Pitmegea River region. Cape Sabine, northwestern 
Alaska. University of Alaska Biological Papers, Number 
10. 

Fay, F. H. 1974. The role of ice in the ecology of 
marine mammals of the Bering Sea. In Oceanography 
of the Bering Sea. Edited by D. W. Hood and E. J. 
Kelley. Institute of Marine Science, University of 
Alaska, Fairbanks, Alaska. 

Fish, J. F. and J. S. Vania. 1971. Killer whale, Orcinus 
orca, sounds repel white whales, Delphinapterus leucas. 
Fishery Bulletin 69: 531-535. 

Fraker, M. A. 1977. The spring migration of white whales, 
Delphinapterus leucas, in the Beaufort Sea. Abstract, 
Proceedings of the Second Conference on the Biology 
of Marine Mammals, San Diego, California. 

Johnson, M. L., C. H. Fiscus, B. T. Otenson, and M. L. 
Barbour. 1966. Marine mammals. //? Environment of the 



1978 



Harrison and Hall.- Beluga Whale Distribution, Alaska 



241 



Cape Thompson region, Alaska. Edited by N. J. Wili- 
movsky and J. N. Wolfe. U.S. Atomic Energy Com- 
mission, Washington, D.C. pp. 877-924. 

Karant, M. 1976. The global navigation system. AOPA 
Pilot 10; 59 61. 

Kellogg, R. 1936. Mammals from a native village site 
on Kodiak Island. Proceedings of the Biological Society 
of Washington 49: 37-38. 

Kleinenberg, S. E., A. V. Yablokok, V. M. Bel'kovich, 
and M .N. Tarasevich. 1964. Beluga (Delphinapterus 
leucas): investigation of the species. Akademiya Nauk 
SSSR, Institut Morfologii Zhivotnykh, Moscow 
(Translated bv Israel Program for Scientific Translation, 
1969). 

McVay, S. 1973. Stalking the arctic whale. American 
Scientist 61(1): 23-37. 

Murie, O.J. 1959. Fauna of the Aleutian Islands and 
Alaska Peninsula. U.S. Fish and Wildlife Service, North 
America Fauna Number 61. 

Nazarenko, Y. I. 1965. Distribution of Beluga in European 
North in winter. Monograph Morskie Mlekopitayush- 
chie, Moscow {Translated by M. Slessers, Naval 
Oceanographic Office, Washington, D.C). 

Sergeant, D. E. and P. F. Brodie. 1969. Body size in white 



whales, Delphinapterus leucas. Journal of the Fisheries 
Research Board of Canada 26: 2561-2580. 

Sergeant, D. E. and P. F. Brodie. 1975. Identity, abun- 
dance and present status of white whales, Delphinapterus 
leucas, in North America. Journal of the Fisheries 
Research Board of Canada 32(7): 1047-1054. 

Sergeant, D. E. and W. Hoek. 1974. Seasonal distribution 
and abundance of bowhead and white whales in the 
eastern Beaufort Sea. In The coast and the shelf of the 
Beaufort Sea. Edited by J. C. Reed and J. E. Sater. 
Arctic Institute of North America, Arlington, Virginia, 
pp. 705-719. 

Scheffer, V. B. and J. W. Slipp. 1948. The whales and 
dolphins of Washington State with a key to the cetaceans 
of the west coast of North America. American Mid- 
land Naturalist 39(2): 257-337. 

Vladykov, V. D. 1944. Etudes sur les mammiferes 
aquatiques. Ill, Chasse, biologie et valeur economique 
du marsouin blanc ou Beluga (Delphinapterus leucas) 
du fleuve et du golfe Saint Laurent. Departement des 
Pecheries, Quebec. 194 pp. 

Received 21 January 1978 
Accepted 26 March 1978 



Sphaeriid Mollusc Populations of Eight Lakes near 
Yellowknife, Northwest Territories 



M. C. Healey 

Department of Fisheries and the Environment, Fisheries and Marine Service, Pacific Biological Station, Nanaimo, 
British Columbia V9R 5K6 

Healey, M. C. 1978. Sphaeriid mollusc populations of eight lakes near Yellowknife, Northwest Territories. Canadian Field- 
Naturalist 92(3): 242-251. 

Sphaeriidae were about twice as abundant in eight lakes near Yellowknife, Northwest Territories as previously reported for 
Precambrian Shield lakes. Depth distribution varied from lake to lake and there appeared to be no predictable distribution of 
Sphaeriidae with depth even among limnologically similar lakes. In the Yellowknife lakes, depth distribution was dictated by 
the relative abundance of individual species and their particular depth distribution in the lake. Nepionic forms were, 
relatively, most abundant in the littoral zone and, seasonally, most abundant in summer and autumn. Nepionic forms were 
more abundant later in the profundal of the lakes than in the littoral, suggesting delay of reproduction in deeper water. In 
general the sphaeriid clam community was dominated by one or two species in each lake and Pisidium conventus was the most 
common dominant, reaching densities in excess of 400/ m- in the profundal of Drygeese Lake. Pisidium conventus vj&i, aho 
the only species common in the profundal, all others being abundant only in the littoral zone, where some species reached 
densities in excess of 400/ m". Three species, Sphaerium lacustre, Pisidium nitidum contortum, and Pisidium nitidum 
pauperculum, were uncommon members of the fauna of northern Precambrian Shield lakes. The presence of these species 
apparently reflects the intermediate nature of the Yellowknife lakes between typical Precambrian Shield lakes and lakes in 
sedimentary basins. The common species in the lakes appear to have similar habitat requirements and variations in abundance 
could not be related to any gross differences in the limnology of the Yellowknife lakes. 

Key Words: Mollusca, Sphaeriidae, populations, northern Canada, clams distribution, abundance. 



Sphaeriid bivalves are a numerically im- 
portant component of the benthic community in 
lakes, and this importance is reflected in a 
considerable literature on these molluscs. Much 
of the literature, however, deals with classical 
taxonomic problems (Herrington 1962; Clarke 
1973) or with growth and reproduction (Heard 
1965; Meier-Brook 1970; Zumoff 1973; Ladle 
and Baron 1969; Danniel and Hinz 1976). 
Published descriptions of the distribution and 
abundance of sphaeriid clams within lakes are 
generally in the form of qualitative notes about 
individual species, or all species are treated 
together as a single group (Adamstone 1924; 
Herrington 1950; Oliver 1960; Rawson 1930, 
1953, 1960; Sarkka 1972). Little attention has so 
far been paid to the numerical abundance of 
individual sphaeriid species. The purpose of this 
report is to describe, quantitatively, aspects of 
the distribution and abundance of sphaeriid 
species in eight lakes near Yellowknife, 
Northwest Territories. 

Description of the Lakes 

Frame, Long, and Grace lakes lie within 
4 km of the city of Yellowknife, while the 
remaining five lakes lie 20 and 40 km away along 



the Yellowknife River valley (Figure 1). They 
range in size from 62 to 547 ha, and in depth 
from 6.5 to 34.5 m (Table 1). Secchi depths 
during open water in 1 97 1 and 1 972 ranged from 
2. 1 m (Grace Lake) to 9 m (Alexie, Baptiste, and 
Drygeese) (Table 1). Conductivity ranged from 
89 ^mho/cm (Alexie) to 332 /xmho/cm (Frame) 
and pH from 7.4 (Baptiste and Long) to 8.5 
(Frame). The chemical composition of the lakes 
was typical of oligotrophic lakes having partial 
shield drainage (Armstrong and Schindler 
1971), except that reactive silicate was low 
(Healey and Woodall 1973a, b). Frame was 
atypical in having high conductivity and above- 
average concentrations of all ions measured, 
with the exception of silicate. This probably 
resulted from the proximity of the lake to the city 
and the addition of ions from local runoff 
(Healey and Woodall 1973a). 

Frame and Long lakes were isothermal 
throughout the open-water season. All the other 
lakes stratified during the summer with a 
thermochne at 8-10 m and some oxygen 
depletion in the hypolimnion. Oxygen satura- 
tion in the hypolimnion never dropped below 
25%, however, except in Grace and Chitty lakes 
(Healey and Woodall 1973a, b). Frame Lake, 



242 



1978 



HEALEY: SPHAERIID MOLLUSC POPULATIONS, NWT 



243 




Figure \. Map of the Yellowknife area. Northwest 
Territories, showing the locations of the eight lakes 
where abundance of sphaeriid molluscs was studied. 



however, became anoxic under the ice in winter 
(G. Brunskill, personal communication). 
Surface temperature reached 18-20°C in July 
and epilimnion temperatures were commonly 
16-18°C throughout the summer. 

The littoral zone (as defined by Ruttner 1963) 
was of limited extent in all the lakes except 
shallow Long and Frame. Littoral substrates 
were generally rocky or sandy and there was 
little rooted vegetation in the deeper lakes. 
Frame and Long lakes had soft substrates 
below 1-m water depth. In the other lakes rocky 
and sandy sediments in the shallow littoral were 
replaced by clay and moss in the deep littoral and 
shallow profundal and silt in the deep profundal. 
Healey and Woodall (1973a, b), Healey and 
Kling (1975), and Healey (1977), give more 
details of the physical, chemical, and general 
biological characteristics of the lakes. 

Materials and Methods 

I took all samples with an Ekman grab, 
1 5 X 1 5 X 22 cm tall. If the jaws or top doors of 
the grab did not close, or the surface of the 
sediment was within 5 cm of the top of the grab I 
repeated the sample. I sieved the samples in the 
field through a 600-^m mesh screen and 
preserved the sieve contents in 5% formalin for 
later sorting by hand under lOX magnification. 

I sampled all eight lakes in 1971, but only 
Alexie, Baptiste, Chitty, and Drygeese in 1972. 1 
sampled the lakes twice in 1971 between June 
and August, the visits to each lake being about 1 
month apart, except for Michel which I sampled 
only once (July). I took 10 grab samples at four 
different locations in shallow lakes on each visit. 
In deep lakes I took five samples from the littoral 



Table 1 — Physical and chemical features of the eight lakes 





Area, 
ha 


Depth (m) 




Secchi (m) 


pH 


Conductivity, 


Lake 


Maximum 


Mean 


Range 


Mean 


/umho/cm 


Frame 


84 


6.5 


1.3 


2.5-3.1 


2.8 


8.5 


332 


Long 


157 


7.0 


— 


4.5-5.0 


4.8 


7.4 


108 


Grace 


62 


18.0 


6.6 


2.1-3.8 


3.0 


8.1 


138 


Michel 


345 


22.0 


— 


— 


5.3 


7.7 


100 


Alexie 


420 


32.0 


11.7 


6.0-9.0 


7.3 


7.5 


89 


Baptiste 


365 


32.0 


11.7 


5.5-9.0 


6.9 


7.4 


101 


Chitty 


325 


20.0 


6.9 


4.8-6.9 


5.7 


7.5 


103 


Drygeese 


547 


34.5 


14.5 


6.0-9.0 


7.2 


7.5 


111 



244 



The Canadian Field-Naturalist 



Vol. 92 



and five from the profundal on each visit. In 
1972 I sampled Alexie, Baptiste, Chitty, and 
Drygeese three times, 29 May - 3 June, 24-21 
July, and 28 September - 5 October, along two 
transects in each lake. Transect 1 had six stations 
(five in Chitty) at equally spaced depths from the 
shallow littoral to the deep profundal, and 
transect 2 had three stations (four in Chitty). I 
took three grab samples at each station on 
transect 1 and two at each station on transect 2. 

Neither the sampling in 1971 nor in 1972 was 
really adequate for a rigorous analysis of 
population sizes in sphaeriid species. The 
appropriate design, one of stratified random 
sampling, could not be established a priori 
because the necessary information on sphaeriid 
distribution and relative abundance was not 
available. 

Variance and mean were strongly correlated 
in the untransformed sample counts, and the 
variance-to-mean ratio normally exceeded 40, 
indicating highly contagious distributions of 
Sphaeriidae. Logarithmic transformation of 
sample counts removed most of the correlation 
between variance and mean. All statistical 
comparisons were, therefore, performed on 
logarithms of the abundance estimates and the 
means presented in the tables are geometric 
means. Abundance is used throughout the paper 
to mean numbers per square metre. 

Individual species tended to occupy specific 
depth zones in the lakes, so that finding a 
representative measure of average abundance 
posed a problem. Values presented in the tables 
are the geometric means for the whole lake or a 
specified portion of the lake. Abundance at the 
typical depth for each species is considered in the 
accounts of individual species. 

My use of geometric means makes direct 
comparison of my results with published data on 
sphaeriid abundance difficult, as published 
values are arithmetic means. In spite of this 
difficulty, I feel that the geometric means are 
more realistic estimates of central tendency in 
the data, and thus better measures of "average" 
abundance. Because the sample counts were 
positively skewed, the geometric means 
presented are less than the corresponding 
arithmetic means. The degree of difference 
depends on the degree of skew, however, so that 
there is no single conversion coefficient. 



Results and Discussion 

The total population of benthic organisms 
retained by the 600-fj.m sieve ranged from 404 to 
3688 organisms/ m- in the lakes, while Sphaeri- 
idae ranged from 42 to 971 /m^. Sphaeriidae 
contributed most to the benthic fauna of Long 
Lake (60%) and least to Baptiste (2.6%) 
(Table 2). By comparison with other oligo- 
trophic lakes on the Precambrian Shield, 
Sphaeriidae were relatively abundant in the 
Yellowknife lakes. Arithmetic mean numbers of 
Sphaeriidae in 17 Saskatchewan lakes ranged 
from 8 to 548/ m^ (Rawson 1960; Koshinsky 
1965). The average in Great Slave Lake was 
175/ m2 (Rawson 1953). These arithmetic means 
are comparable in size with the geometric means 
for the Yellowknife lakes, but the arithmetic 
means will be higher than the corresponding 
geometric means. Arithmetic means for the 
Yellowknife lakes were approximately 925-1 198 
sphaeriids/m^. Thus, the comparison, although 
tentative because of the different averaging 
technique used, suggests that Sphaeriidae were 
about twice as abundant in the Yellowknife lakes 
as reported elsewhere. Percentage contribution 
to the bottom fauna was similar to that in other 
lakes, however, except for Long Lake, in which 
it was high. The Yellowknife lakes were rich in 
bottom fauna generally, not just Sphaeriidae 
(Healey 1977). 

Sphaeriidae were present at all depths 
sampled in Alexie, Baptiste, Chitty, and 
Drygeese in 1972, but their abundance varied 
with depth (Table 3). The depth distribution was 
also unique to each lake. In Alexie there were 
two peaks of abundance, one in the shallow 
littoral (757/ m-) and one in the mid-profundal 
(739/ m-), with minima in the shallow profundal 
and deep profundal. In Baptiste there was a 
single peak in the shallow littoral (840/ m-) and 
numbers declined rapidly with increasing depth. 
In Chitty there was a single peak in the deep 
littoral (890/ m-) with minima in the shallow 
littoral and profundal. Drygeese had peaks in 
abundance in the shallow littoral (381/m-) and 
mid-profundal (624/ m-) similar to abundance 
peaks in Alexie, but the peaks were less 
prominent. Comparison of littoral and pro- 
fundal samples from Grace and Michel lakes in 
1971 indicated that Sphaeriidae were abundant 
only in the littoral zone (Table 4), suggesting 



1978 



HEALEY: SPHAERIID MOLLUSC POPULATIONS, NWT 



245 



Table 2 — Percentage composition of the Sphaeriidae in the eight lakes. Abundance estimates are for 1971 in Frame, Long, 
Grace, and Michel and for 1971 and 1972 averaged in Alexie, Baptiste, Chitty, and Drygeese 













Lake 










Frame 


Long 


Grace 


Michel 


Alexie 


Baptiste 


Chitty 


Drygeese 


Total benthos/ m- 


3205 


535 


404 


853 


2574 


2808 


935 


3688 


Total Sphaeriidae/ m2 


971 


321 


42 


58 


296 


73 


72 


177 


Total Sphaeriidae % 


30.3 


60.0 


10.4 


6.8 


11.5 


2.6 


7.7 


4.8 


Immature and adult forms % 


100 


67 


74 


59 


71 


57 


82 


68 


Nepionic forms % 





33 


26 


41 


29 


43 


18 


32 


Species composition% 


















Pisidium conventus 


0.9 


13.5 


8.3 


39.4 


53.6 


27.7 


61.0 


77.0 


lilljeborgi 


3.3 


21.0 


22.5 


25.6 


12.6 


3.5 


7.0 


5.2 


nitidum 


23.7 


10.2 


7.5 


0.0 


2.8 


3.2 


<0.1 


2.9 


nitidum-contortum 


0.9 


6.4 


3.8 


9.8 


12.5 


19.0 


10.0 


5.6 


nitidum-pauperculum 


0.0 


0.0 


0.0 


0.0 


<0.1 


0.0 


0.0 


0.0 


ventricosum-rotundatum 


6.6 


8.2 


5.0 


2.0 


5.4 


14.5 


8.7 


5.7 


casertanum 


0.0 


19.3 


40.0 


13.8 


1.1 


3.6 


4.3 


0.0 


subtruncatum 


6.6 


8.6 


0.0 


0.0 


8.2 


24.1 


3.0 


1.6 


walkeri 


0.0 


2.7 


0.0 


0.0 


0.6 


1.6 


1.7 


0.0 


ferrugineum 


5.6 


0.0 


0.0 


0.0 


2.3 


2.9 


3.4 


0.0 


idahoense 


0.0 


6.4 


12.5 


9.8 


0.5 


0.0 


0.4 


0.0 


cf. milium 


0.0 


0.5 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


Sphaerium nitidum 


4.0 


2.7 


0.0 


0.0 


0.1 


0.0 


0.5 


1.9 


lacustre* 


48.4 


0.7 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 



*Subgenus Musculium (Link). 

depth distributions in these lakes similar to that 
in Baptiste. Rawson (1930, 1953) and Oliver 
(1960) described the depth distribution of 
Sphaeriidae in Lake Simcoe, Great Slave Lake, 
and Lac la Ronge. In Lake Simcoe Sphaeriidae 
were most abundant between 15 and 20 m 
(120/ m^) and least abundant near the surface 
and in the deep profundal. In Great Slave, 
Sphaeriidae were most abundant in the to 5-m 
depth zone (636/ m^), and declined continuously 
in abundance with depth. In Lac la Ronge, the 
depth distribution was different in Hunter Bay 
and the main lake. In Hunter Bay, Sphaeriidae 
were most abundant (2000/ m^) at 15-20 m 
depth and least abundant in shallow water. In 
the main lake, however, maximum abundance 
was in the littoral ( 1 50-200/ m^). Clearly, there is 
no predictable pattern of sphaeriid abundance 
with depth, even among limnologically similar 
lakes. Presumably the depth distribution of 
Sphaeriidae in the lakes is related to the species 
mix, and the particular limnological conditions 
in the lakes. There were no obvious differences in 
the limnology of Alexie, Baptiste, Chitty, and 
Drygeese lakes that would account for the 
different distributions, however, (Healey and 
Woodall 1973b), nor were there sufficient 



differences in species composition among these 
four lakes to account for the differences in 
distribution (Table 2). 

Many of the Sphaeriidae examined were 
nepionic forms (recent post-embrionic forms too 
immature for species identification). The 
proportion of nepionic forms in the populations 
ranged from 0% in Frame to 43% in Baptiste 
(Table 2). Why there were no nepionic forms in 
Frame Lake is not clear. Presumably the 
presence of nepionic forms reflects recent release 
of litters from the parent animals. Their 
abundance should be greatest in early summer 
when most species release litters (Ladle and 
Baron 1969; Heard 1965; Danniel and Hinz 
1976). Nepionic forms constituted 5% or less of 
samples taken in early spring 1972 from Alexie, 
Baptiste, Chitty, and Drygeese. Maximum 
contribution to samples was in summer in Alexie 
and Drygeese (21 and 39%) and in autumn in 
Baptiste and Chitty (72 and 14%) (Table 5). 
These observations suggest that summer and 
autumn were the most important periods for 
release of embryos. Nepionic forms were most 
abundant in the littoral of all the lakes (Table 4), 
and reached their greatest proportional 
representation in the shallow littoral in Alexie 



246 



The Canadian Field-Naturalist 



Vol. 92 



Table 3— Abundance of Sphaeriidae at different depths in Alexie, Baptiste, Chitty, and Drygeese lakes in 1972 



P. conventus 

lilljeborgi 

nitidum 

nitidum-contortum 

ventricosum-rotundatum 

casertanum 

subtruncatum 

walkeri 

ferrugineum 

idahoense 
S. nitidum 
Nepionic forms 

Total Sphaeriidae 



P. conventus 

lilljehorgi 

nitidum 

nitidum-contortum 

ventricosum-rotundatum 

casertanum 

subtruncatum 

walkeri 

ferrugineum 

idahoense 
S. nitidum 
Nepionic forms 

Total Sphaeriidae 



123 

7 

19 

128 

12 

8 

80 



21 



2 

357 



36 
31 
2 
2 
2 



49 



Depth 



0-5 5-10 10-15 15-20 20-25 25-30 0-5 5-10 10-15 15-20 20-25 25-30 30-35 



128 

173 

3 

28 

45 

10 

21 



13 

9 



304 



757 734 



15 331 

3 79 



66 

49 

44 

21 

18 

42 

5 

6 

229 



Alexie 



77 
85 
12 




12 



90 



3 



276 93 
Chitty 



156 
12 


< 1 

10 
3 

6 

2 
1 

25 



315 



140 890 216 



321 



739 




739 



68 



13 




167 



6 
82 



Baptiste 



66 


16 


77 


13 


8 





124 


20 





80 







27 







147 


33 


1 





8 





6 


8 


5 



25 



26 



377 


186 


< 1 


7 6 





840 


279 


83 


32 32 
Drygeese 


2 



17 


56 


116 


31 


4 








10 





33 


2 





20 


1 






249 



475 



36 



118 



13 




108 



100 



113 



22 



381 161 224 349 624 



3 
16 



Table 4 — Abundance/ m- of Sphaeriidae in the littoral (L) and profundal (P) zones of the eight lakes. Data for Alexie, 
Baptiste, Chitty, and Drygeese lakes are for 1971 and 1972 averaged, the others are 1971 data only 



Frame 


Long 
L 


Grace 
L P 


Michel 


Alexie 


Baptiste 
L P 


Chitty 
L P 


Drygeese 


L 


L P 


L P 


L P 



P. conventus 


9 


29 


112 





369 


1 


150 


123 


48 


10 


140 


14 


93 


88 


lilljeborgi 


32 


45 


307 





240 





68 


5 


12 





24 


< 1 


27 





nitidum 


231 


22 


103 











14 





23 





2 





13 





nitidum-contortum 


8 


14 


51 





92 





94 





26 





45 





19 





nit idum-pauperculum 




















< 1 























ventricosum-rotundatum 


64 


17 


68 





18 





39 


< 1 


50 


< 1 


47 


< 1 


19 


2 


casertanum 





42 


549 





129 





12 





13 





16 


< 1 








subtruncatum 


64 


18 














43 


< 1 


69 


< 1 


12 


< 1 


4 





walkeri 





6 














5 


< 1 


3 





6 











ferrugineum 


54 

















22 





6 


< 1 


8 


< 1 








idahoense 





14 


168 





92 





2 











2 


< 1 








cf. milium 





1 






































S. nitidum 


39 


6 














3 


< 1 








3 





10 





lacustre 


470 


2 






































Nepionic forms 





105 


467 





664 





341 


8 


264 


2 


117 


< 1 


90 


32 


Total Sphaeriidae 


971 


321 


1825 





1604 


1 


793 


137 


514 


13 


422 


15 


275 


122 



1978 



HEALEY: SPHAERIID MOLLUSC POPULATIONS, NWT 



247 



Table 5 — Seasonal variation in nepionic forms/ m- and proportional representation of nepionic forms by depth zone in 
Alexie, Baptiste, Chitty, and Drygeese lakes in 1972. Sp = spring, Su = summer, Au — autumn 







Alexie 






Baptiste 






Chitty 






Drygeese 






Sp 


Su 


Au 


Sp 


Su 


Au 


Sp 


Su 


Au 


Sp 


Su 


Au 


Total Sphaeriidae 
Nepionic forms 


666 

3 


241 
51 


221 
21 


192 

5 


59 
19 


65 

47 


233 
11 


334 
9 


238 
34 


214 
5 


162 
63 


226 
12 


% nepionic 

By depth zone, m 
0-5 


< 1 

27 


21 
62 


10 

53 


2 
29 


32 
80 


72 
44 


5 
22 


3 
58 


14 
43 


2 
12 


39 
51 


5 

72 


5-10 


16 


64 


33 


30 


65 


82 


31 


9 


33 





84 


49 


10-15 





47 


56 


9 


26 


92 


15 





18 


29 


78 


35 


15-20 





24 








54 


57 








1 


20 


80 





20-25 














100 


100 








8 


28 


4 


25-30 





























33 





30-35 




















100 


100 






and Chitty and in the deep littoral in Baptiste 
and Drygeese (Table 3). 

The depth distribution of nepionic forms 
during the spring, summer, and autumn of 1972 
in Alexie, Baptiste, Drygeese, and Chitty 
suggests that embryos are released earlier in the 
shallow water than in the deep water. Drygeese 
was exceptional in having nepionic forms in the 
profundal in spring, but the numbers were small 
(Table 5). 

The greater proportion of nepionic forms in 
the littoral suggests that reproductive activity is 
greater there. The proportion of nepionic forms 
in the littoral and profundal, however, must also 
be related to the life history patterns of the 
species. The profundal of Alexie, Baptiste, 
Chitty, and Drygeese was dominated by 
Pisidium conventus, which is relatively long- 
lived and has small litters (Heard 1965). The 
littoral zone of these lakes, on the other hand, 
had numerous species, some of which are short- 
lived and/ or have large litters (Heard 1965). 
Thus, species composition alone may account 
for the greater proportion of nepionic forms in 
the littoral. 

Twelve species of Pisidium and two of 
Sphaerium occurred in the lakes. Pisidium 
conventus was the dominant species in Michel, 
Alexie, Chitty, Baptiste, and Drygeese, 
composing 28-65% of all Sphaeriidae. 
Sphaerium lacustre was dominant in Frame 
Lake, P. lilljeborgi in Long Lake, and P. 
casertanum in Grace Lake (Table 2). Four 
species were present in all the lakes {P. 
conventus, P. lilljeborgi, P. nitidum contortum. 



P. ventricosum rotundatum), and two were 
present in only one lake {P. nitidum pauper- 
culum, and P. cf. milium). Long and Alexie 
lakes had the most species (12), while Michel 
had fewest (6). One species was numerically 
dominant over all others in five of the lakes, 
while two species dominated in the other three. 
Comparison of species composition and relative 
abundance indicates that Frame Lake was 
different from all the others. Grace and Long 
lakes were similar in that they were dominated 
by P. lilljeborgi and P. casertanum, but in 
species composition Grace resembled Michel, 
and Long resembled Alexie, Baptiste, and 
Chitty. Drygeese resembled Alexie, Baptiste, 
and Chitty in its dominant species but was 
similar to Michel in overall composition. 

The mix of species recorded from the lakes is 
fairly typical of northern lakes, most species 
being those which are considered cold-loving, or 
which have previously been described from 
northern lakes (Herrington 1950, 1962; Heard 
1963; Oliver 1960; Holmquist 1975; Clarke 
1973). The occurrence of only one or two 
abundant species in each lake community is 
consistent with observations on Great Slave and 
Athabaska lakes (Herrington 1950; Rawson 
1947, 1953) where only P. conventus and P. 
subtruncatum were common species, the others 
being represented by only a few specimens in 
hundreds of dredgings. 

The characteristic depth distributions of 
Sphaeriidae in the lakes appear partially related 
to the relative abundance of different species, if 
not directly to the mix of species. Pisidium 



248 



The Canadian Field-Naturalist 



Vol. 92 



conventus had a bimodal depth distribution, 
with peaks in the Httoral and mid-profundal 
(Table 3). The dominance of this species in 
Alexie and Drygeese resulted in the peak in 
abundance in the profundal. The other species 
were restricted to the littoral, or were rare in the 
profundal (Table 3). Species other than P. 
conventus contributed most to the community in 
Baptiste so that there was only a single peak in 
abundance in the littoral in this lake. Species 
that were most abundant in the shallow littoral 
in Baptiste and Drygeese tended to be more 
abundant in the deep littoral of Alexie and 
Chitty (Table 3). This difference in distribution 
among littoral species resulted in a peak of 
abundance in the deep littoral of Chitty rather 
than the shallow littoral as in Baptiste. Why the 
distribution of these species differed among the 
lakes is not clear. Similar subtle differences 
between Alexie and Chitty as a pair and Baptiste 
and Drygeese as a pair were evident in other 
biological parameters, however (Healey and 
Kling 1975; Healey 1977). 

I subjected the estimates of abundance for 
Alexie, Baptiste, Chitty, and Drygeese lakes to 
two analyses of variance (a Lake X Transect 
X Season X Species analysis of the 1972 data 
and a Lake X Year X Species analysis of the 
combined 1971 and 1972 data). In the analysis of 
the 1972 data there were significant differences 
only among lakes (F = 9.199, P<0.01) and 
species (F = 41.559, P< 0.001), not among 
seasons and transects. The lake by species- 
interaction term was also significant (F = 1.979, 
P < 0.05), indicating different species con- 
tributions in the lakes. In the analysis of the 
combined 1971 and 1972 data differences among 
species were significant (F = 25.6, jP< 0.001) as 
were interactions among lakes and species 
(F = 2.262, P<0.05) and species and years 
(F = 3.459, P<Q.O\). Differences between 
years and lakes were not significant. The species- 
by-year interaction suggests that individual 
species may have varied in abundance from year 
to year. Inspection of the data on abundance, 
however, revealed no obvious and consistent 
changes in species abundance in the four lakes. 

It is difficult to know how much confidence to 
place in these analyses, especially the inter- 
action terms, because of the high variability in 
individual abundance estimates, and the 



different sampling procedures used in 1971 and 
1972. They do indicate, however, that the 
differences in abundance observed among the 
Yellowknife lakes were statistically significant, 
and that the differences in relative species 
composition observed among the four lakes 
sampled in 1972 were also significant. 

Cluster analysis of the sample data for Alexie, 
Baptiste, Chitty, and Drygeese (Association 
based upon the Euclidian distance between 
species in the species X sample matrix; see 
Duewer et al.' ) indicated significant separation 
between P. conventus and all other species, but 
no other significant groupings of species. 
Pisidium conventus presumably separated out 
because of its occurrence alone in profundal 
samples. Each of the remaining common species 
was found together with almost every other 
species in the samples, suggesting little or no 
habitat segregation within the lakes, at least on 
the scale of an Ekman dredge sample. The results 
do suggest, however, that for the Yellowknife 
lakes it is appropriate to compare the littoral 
zones of the lakes separately from the profundal 
zones. This puts a somewhat different perspec- 
tive on the comparison of total abundance and 
the contribution of individual species in the lakes 
(Table 4). Comparison of Frame and Long 
lakes with the others also becomes more 
meaningful, since Frame and Long had no 
profundal. When only littoral zones are 
compared, Frame and Long lakes no longer 
stand out as having the most sphaeriids. Grace 
and Michel lakes, which on a whole-lake basis, 
had relatively small sphaeriid populations, had 
the densest populations in their littoral, almost 
twice as dense as Frame Lake (Table 4). 
Sphaeriidae were absent from the profundal of 
Grace, and only a few P. conventus occurred in 
the profundal of Michel. Sphaeriidae were least 
abundant in the littoral zones of Long and 
Drygeese lakes. 

Even in the littoral zone, P. conventus was the 
most abundant species overall (Table 4). The 
only other species that could be generally 



ID. L. Duewer. J. R. Koskinen. B. R. Kowalski. 1977. 
"ARTHUR": a package of programs for pattern recogni- 
tion. Available from B. R. Kowalski, Laboratory for 
Chemometrics, Department of Chemistry, BG-IO, 
University of Washington, Seattle, Washington 98195, 
USA. 



1978 



HEALEY: SPHAERIID MOLLUSC POPULATIONS, NWT 



249 



considered abundant over all the lakes was P. 
lilljeborgi. Both these species are widely 
distributed in central and arctic Canada (Clarke 
1973), and P. conventus is one of the best studied 
of the Sphaeriidae (Heard 1963). Both are 
reported from a wide variety of substrate types 
(Herrington 1962) and are known to occur to 
considerable depth (Heard 1963). Meier-Brook 
(1969), however, reported a significant pref- 
erence for fine substrates in P. lilljeborgi. In the 
Yellowknife lakes, P. conventus had a bimodal 
depth distribution, as previously noted. The 
greatest population density observed for this 
species was 739/ m^ at 20-25 m depth in Alexie, 
and maximum abundance was generally below 
the thermocline in this species. The presence of a 
second maximum in the littoral zone, however, 
attests to the adaptability and probable high 
competitive ability of this species. Pisidium 
lilljeborgi was most abundant in the littoral 
zone, reaching maximum densities of 307/ m^ 
and 240/m' in Grace and Michel lakes 
(Table 4). Pisidium lilljeborgi did not occur 
below the 15-20 m depth stratum in the 
Yellowknife lakes. This is at odds with previous 
records for the species, which show it occurring 
to 50 fathoms (92 m) (Heard 1963). Pisidium 
lilljeborgi was most abundant in Grace and 
Michel lakes, but was an important contributor 
to the fauna of the other lakes (Table 4). 

Pisidium nitidum, P. casertanum, P. 
idahoense, and S. lacustre were each abundant 
in one of the eight lakes, but were relatively rare 
or absent from most of the lakes. Pisidium 
nitidum and S. lacustre were abundant only in 
Frame Lake, although P. nitidum was also 
moderately abundant in Grace Lake (Table 4). 
Pisidium nitidum is widely distributed in central 
and arctic Canada and is found on a wide variety 
of substrates, although Meier-Brook (1969) 
identified a significant preference for coarser 
substrates in this species. The species occurred 
only in the littoral zone, and its abundance in the 
soft substrate of Frame Lake appears contra- 
dictory to its supposed preference for coarse 
substrates. Spaherium lacustre has been 
recorded from only a few localities north of 
60° N (Clarke 1973) and is reported to have a 
preference for muddy substrates (Herrington 
1962). This is one of three species recorded from 
the Yellowknife lakes that is not typically a 
northern species. Its abundance in Frame Lake 



may be related to the presence of soft organic 
substrates and atypical ionic concentrations in 
the lake. Pisidium casertanum was abundant 
only in Grace Lake and moderately abundant in 
Michel. This species is nearly cosmopolitan, and 
is probably the most common Pisidium species 
in Canada (Clarke 1973). It is, therefore, 
surprising that P. casertanum was not more 
common in the Yellowknife lakes. Conditions in 
these lakes appear to have favored P. conventus 
and P. lilljeborgi over P. casertanum. In a survey 
of lakes on the north slope and arctic coastal 
plain in Alaska and western Canada, Holmquist 
(1975) found P. casertanum more commonly 
than P. conventus. Pisidium idahoense was 
abundant only in Grace Lake (Table 4). This 
species is widely distributed in Precambrian 
Shield lakes, and is generally considered to be 
cold-loving (Herrington 1962). Again, it is 
surprising that this species was not more 
abundant. 

Pisidium nitidum contortum and P. ventri- 
cosum rotundatum, although never abundant, 
made a significant contribution to the fauna of 
most of the lakes (Table 4). Pisidium nitidum 
contortum is the second species not typically 
found in the north. Living populations of P. 
nitidum contortum have not previously been 
reported from outside central Ontario, although 
fossils have been reported from Saskatchewan 
and northern Alberta. The presence of 
apparently healthy specimens in the Yellow- 
knife lakes confirms the hypothesis of a 
historically wide distribution of this morph and 
demonstrates its continued survival in locations 
outside Ontario (Clarke 1973). 

The remaining species were moderate to rare 
in abundance in the lakes, never exceeding 
50-70/ m2 in the littoral zone. The third distri- 
butional anomaly is P. nitidum pauperculum, 
four specimens of which occurred in one of the 
samples from Alexie Lake. This species has not 
previously been reported from lakes on the 
Precambrian Shield, although it is known from 
shield margin lakes (Clarke 1 973). Its presence in 
the Yellowknife lakes may be due to the 
relatively high calcium content of these lakes in 
comparison with other shield lakes (Healey and 
Woodall 1973b). 

Although the factors determining the 
abundance of individual sphaeriid species in the 
eight lakes cannot be identified at this stage. 



250 



The Canadian Field-Naturalist 



Vol. 92 



certain conjectures may be made. The sphaeriid 
communities in the lakes, ahhough fairly typical 
of northern lakes, included species {S. lacustre, 
P. nitidum contortum, and P. nitidum pauper- 
culum) indicative of more nutrient-rich or more 
southern lakes. This is in keeping with the 
chemical characteristics of the lakes, which were 
similar to those of lakes on the margin of the 
shield rather than to those of lakes with a 
completely shield drainage (Armstrong and 
Schindler 1972). Further, the degree of 
difference in community structure and abun- 
dance of individual species among the lakes was 
related to the degree of difference in their 
limnological conditions. Alexie, Chitty, 
Baptiste, and Drygeese were most similar in their 
limnology and in their sphaeriid communities. 
Frame and Long lakes were most unique, 
limnologically, especially Frame, and this was 
reflected in their sphaeriid communities. It 
would be surprising if the sphaeriid community 
were not related to the limnological conditions 
in the lakes; however, the high degree of 
association among the species in the littoral 
zones of the lakes suggests that all the common 
species were adapted to a wide variety of living 
conditions. The reasons for the considerable 
differences in their abundance among the lakes 
must, therefore, have to do with rather subtle 
differences in the lakes, rather than with general 
limnological conditions. Further study of the 
limnological requirements of the individual 
species will be required before it will be possible 
to explain differences in species composition and 
abundance of the sort described here. 

Acknowledgments 

Various technical assistants participated in 
the collecting, sorting, and cataloguing of 
specimens, especially K. D. Rowes. Species 
were identified by L. Kalas, Department of 
Fisheries and Environment, Inland Waters 
Directorate, Burlington, Ontario. D. Rosen- 
berg criticized a draft of the manuscript. 

Literature Cited 

Adamstone, F. B. 1924. The distribution and economic 
importance of the bottom fauna of Lake Nipigon with an 
Appendix on the bottom fauna of Lake Ontario. 
University of Toronto Studies, Biological Series, 
Publications of the Ontario Fisheries Research 
Laboratory 24: 33-100. 



Armstrong, F.A.J, and D. W. Schindler. 1972. Pre- 
liminary chemical characterization of waters in the 
Experimental Lakes Area, Northwestern Ontario. 
Journal of the Fisheries Research Board of Canada 28: 
171-187. 

Clarke, A. H. 1973. The freshwater molluscs of the 
Canadian interior basin. Malacologia 13: 1-509. 

Danniel, Use and W. Hinz. 1976. Zur Biologic von 
Pisidium anmicum O. F. Muller (Bivalvia). Archiv fur 
Hydrobiologie 77: 213-225. 

Healey, M. C. 1977. Experimental cropping of lakes. 4, 
Benthic communities. Fisheries and Marine Service 
Technical Report 711: 1^8. 

Healey, M. C. and H.J. Kling. 1975. Experimental 
cropping of lakes. 3, Phytoplankton and zooplankton. 
Fisheries and Marine Service Technical Report 533. 
27 pp. 

Healey, M. C. and W. L. Woodall. 1973a. Limnological 
surveys of seven lakes near Yellowknife, Northwest 
Territories. Fisheries Research Board of Canada Tech- 
nical Report 407. 34 pp. 

Healey, M. C. and W. L. Woodall. 1973b. Experimental 
cropping of lakes. II. Physical and chemical features of 
the lakes. Fisheries Research Board of Canada Tech- 
nical Report 384. 19 pp. 

Heard, W. H. 1963. The biology of Pisidium (Neopisi- 
dium) conventus Clessin (Pelesypoda; Sphaeriidae). 
Papers of Michigan Academy of Science, Arts and Letters 
48: 77-86. 

Heard, W. H. 1965. Comparative life histories of North 
American pill clams (Sphaeriidae; Pisidium). Mala- 
cologia 2: 381-411. 

Herrington, H. B. 1950. Sphaeriidae of Athabaska and 
Great Slave lakes. Northwestern Canada. Canadian 
Field-Naturalist 64: 25-32. 

Herrington, H. B. 1962. A revision of the Sphaeriidae of 
North America (Mollusca: Pelecypoda). Miscellaneous 
Publications of the Museum of Zoology, University of 
Michigan 118: 1-74. 

Holmquist, C. 1975. Lakes of Northern Alaska and North- 
western Canada and their invertebrate fauna. Zoologische 
Jahrbuecher Abteilung Systematik Oekologie und 
Geographic der Tiere 102: 333^84. 

Koshinsky, G. D. 1965. Limnology and fisheries of five 
Precambrian head water lakes near Lac la Ronge, 
Saskatchewan. Saskatchewan Department of Natural 
Resources, Fisheries Report #7. pp. 1-52. 

Ladle, M. and F. Baron. 1969. Studies on three species of 
Pisidium (Mollusca: Bivalvia) from a chalk stream. 
Journal of Animal Ecology 38: 407-413. 

Meier-Brook, C. 1969. Substrate relations in some Pisi- 
dium species (Eulamellibranchiata: Sphaeriidae). Mala- 
cologia 9: 121-125. 

Meier-Brook, C. 1970. Untersuchungen zur Biologic einiger 
Pisidium-Arten (Mollusca; Eulamellibranchiata; Sphaeri- 
idae). Archiv fur Hvdrobiologie Supplement B 38(1/2): 
73-150. 

Oliver, D. R. 1960. The macroscopic bottom fauna of Lac 
la Ronge, Saskatchewan. Journal of the Fisheries Research 
Board of Canada 17: 607-624. 

Rawson, D. S. 1930. The bottom fauna of Lake Simcoe 
and its role in the ecology of the lake. University of 



1978 



HEALEY: SPHAERIID MOLLUSC POPULATIONS, NWT 



251 



Toronto Studies, Biological Series, Publications of the 
Ontario Fisheries Research Laboratory 40: 1-83. 

Rawson, D. S. 1947. Lake Athabaska In Northwest Can- 
adian Fisheries Surveys in 1944-1945. Bulletin of the Fish- 
eries Research Board of Canada 72: 69-85. 

Rawson, D. S. 1953. The bottom fauna of Great Slave 
Lake. Journal of the Fisheries Research Board of Canada 
10: 486-520. 

Rawson, D. S. 1960. A limnological comparison of twelve 
large lakes in northern Saskatchewan. Limnology and 
Oceanography 5: 195-211. 



Ruttner, F. 1963. Fundamentals of limnology. University 

of Toronto Press, Toronto, pp. 1-295. 
Sarkka, J. 1972. The bottom macrofauna of the oligo- 

trophic lake Konnevesi, Finland. Annales Zoologici 

Fennici9: 141-146. 
Zumoff, C. H. 1973. The reproductive cycle of Sphaerium 

simile. Biological Bulletin (Woods Hole) 144(1): 212-228. 



Received 30 August 1977 
Accepted 9 March 1978 



Summer Movements and Feeding by Moose in 
Western Quebec 



R. JOYAL and B. SCHERRER 

Departement des Sciences Biologiques, Universite du Quebec a Montreal, Montreal, Quebec H3C 3P8 

Joyal, R. and B. Scherrer. 1978. Summer movements and feeding by Moose in western Quebec. Canadian Field-Naturalist 
92(3): 252-258. 

Summer observations on activity of Moose (Alces alces) in western Quebec showed that diurnal aquatic feeding lasted for less 
than 1 h. During most of the day Moose ate the leaves of shrubs orruminates. White B\rc\\( Betula papyrifera) dLnd willows 
(Salix spp.) were preferred. Wind (up to 24 km/h) and rain did not affect movements on roads. Sixty percent of these 
movements occurred at night. After the first half of August, Moose leave their summer range but come back again in early 
September at the beginning of the rut period. 

Key Words: Moose, summer activity, movements, summer diet, habitat, western Quebec. 

Des observations sur les activites estivales de I'orignal {A Ices alces) dans I'ouest du Quebec ont demontre que durant la periode 
diurne, I'orignal se nourrissait de plantes aquatiques durant moins de 1 h en moyenne. Le reste de lajourneeetait utilise pour 
ringestion et la rumination de feuilles d'arbustes dont les preferes etaient le bouleau blanc {Betula papyrifera) et les saules 
{Salix spp.). Soixante pourcent de deplacements sur les chemins se firent la nuit. La pluie et les vents (inferieurs a 24 km/h) 
n'affecterent pas ces deplacements. Apres la deuxieme semaine d'aout, les orignaux quittaient temporairement leur territoire 
d'ete pour y revenir a la periode d'accouplement qui semblait commencer vers la deuxieme semaine de septembre. 

Mots clefs: orignal, activites estivales, deplacements, nourriture estivale, habitat, ouest du Quebec. 



The summer activities and diet of North 
American Moose are poorly documented. In a 
review of food habit studies (Peek 1974), only 
nine of 41 reports offered summer observations, 
of which three were from central and eastern 
Canada. Bouchard (1967) and de Vos (1958) 
also worked in central and eastern Canada. 
Bouchard (1967) reported that Moose on the 
Peribonka River ceased aquatic feeding by mid- 
August while de Vos (1958) observed aquatic 
feeding in Ontario until the month of October. 

De Vos (1958) noted that the distribution of 
Moose along the lakes and rivers in Ontario 
seemed to be related to the abundance and the 
distribution of aquatic vegetation, but on the 
Peribonka (Bouchard 1967) occurrence of 
Moose was related also to weather conditions. 
Summer activity was also noted by Grenier 
(1974), who observed most road kills of Moose 
at night. Recently in Maine, Dunn (1976) found 
that in summer. Moose inhabited mixed stands 
and that the peak of aquatic feeding occurred 
from the fourth week of June until the fourth 
week of July. Dunn (1976) observed that the 
peak of daily aquatic activity took place between 
1200 and 1400 hours in contrast to observations 
of Bouchard (1967) and de Vos (1958) who 
noted aquatic activity mostly at sunrise and at 



sunset. This aspect of Moose behavior is 
important in nature-observation programs in 
parks. 

The purpose of this study was to obtain a 
better knowledge of the diet and use of habitat 
by Moose in summer. Feeding activity in both 
terrestrial and aquatic habitats was examined. 
Daily activity, and the influence of weather on 
the movements of moose were also studied. The 
study was part of a long-term project on Moose 
and their habitat in western Quebec. 

The study area was located in and near Mont- 
Tremblant Provincial Park, about 120 km north 
of Montreal. It is in the Laurentian Section of 
the Great Lakes - St. -Lawrence Region (Rowe 
1972). The gently hilly terrain is covered with a 
mixed forest dominated by Black Spruce {Picea 
mariand). White Birch {Betula papyrifera). 
Trembling Aspen (Populus tremuloides). 
Balsam Fir {Abies balsamea), and Yellow Birch 
{Betula alleghaniensis). Fire succession stands of 
Jack 'P\nt{Pinus divaricata) occupy sandy areas. 
Altitude varies between 400 m and 800 m. The 
region abounds with numerous lakes which 
provide plentiful summer food for Moose. The 
area is known to support about four Moose per 
100 km- (Michel Crete, personal communi- 
cation). 



252 



1978 



JOYAL AND SCHERRER: MOOSE IN WESTERN QUEBEC 



253 



Methods 

Feeding and Diet 

Aquatic feeding was observed at a eutrophic 
pond approximately 15 km east of Mont- 
Tremblant Park. Observations 2 or 3 days per 
week from daybreak until dusk were made from 
28 June to 15 September 1972, and totalled 
370 h. The pond provided good food supply, but 
was situated near an inhabited area. Observa- 
tions on Moose feeding were tallied along with 
the data, the time of day, the length of feeding 
periods, and the weather conditions. 

One mature bull, one young bull, and a cow 
with two calves were using the pond at the start 
of observations. One calf was hit by a car in late 
June, however, and the other calf disappeared in 
mid-July. When observations began at the end 
of June, the Moose had already used the pond 
for almost 2 wk. By the end of July, the pool was 
almost entirely covered with Bullhead-lily 
(Nuphar variegatum). Bur-reed {Sparganium 
angustifolium), and Watershield {Brasenia 
schreberi) among which grew some species of 
submerged pond weed {Potamogeton spp.). 
Moose grazed on all species and no effort was 
made to ascertain the proportion of each in the 
diet. 

Terrestrial feeding was observed in 1973 near 
Lac Laverdiere, a remote area in the northern 
part of the Mont-Tremblant Park. This study 
area was situated at the end of a lumber road. 
The area was logged 10 yr before and is con- 
sidered good Moose range. Although it was also 
clear cut, many patches of conifers were left and 
served as winter cover. Because of its remote 
location, the area was almost ignored by fisher- 
men, permitting observations of undisturbed 
animals, a situation contrasting with the 
previous year's conditions. 

Terrestrial feeding was determined by a 
modified version of the aggregate percentage 
method of Passmore and Hepburn (1955). 
Seventy-seven plots, 1 X 20 m, were randomly 
located in feeding sites. In each plot, the number 
of stems per species (availability) was tallied. 
Also, the percentage of available current-year 
growth (up to 2 m) with leaf removal evidence 
(degree of browsing) was estimated for each stem 
of each species, and each stem was assigned to 
one of three percentage classes (Passmore and 
Hepburn 1955). 



The relative density, or the availability of each 
species, was calculated by the mean stem density 
per plot. Preference is based on the ratio of 
availability over the importance of each species 
in the diet (Joyal 1976). 

When possible, direct observations of terres- 
trial activity by Moose were noted in order to 
evaluate the relative importance of terrestrial 
feeding. 

Habitat Use and Movements 

Habitat use and daily movements were also 
studied in the same area. Distribution of use 
between habitats was first assessed by a pre- 
liminary track survey in June. Afterwards, 15 
stations were chosen which took into account 
habitat diversity and occurrence of tracks. A 
station consisted of a 100-m section of sandy 
road (transect); this is a version of Wright's 
method (Bider 1968). The 15 sand transects were 
dispersed along a 16-km secondary road near 
major habitats such as ponds, swamps, and 
cutover. The number of transects was limited by 
the time required to complete the 16-km circuit. 
Some habitat can be represented by one to three 
transects. 

The circuit was visited four times daily from 
8 July to 3 1 August with the schedule alternating 
weekly as follows: one week at 0000, 0600, 1200, 
and 1800 hours; the next week at 0300, 0900, 
1500, and 2100 hours. At the start of each run 
(tracking session), weather conditions such as 
cloudiness, rain, temperature, and wind velocity 
were noted. At each run, tracks of moose found 
in a transect were recorded and erased with a 
broom. We calculated tracks/ transect ratio for 
habitat use and tracks/ run ratio for daily 
activity and weather influence on this activity. 
Chi-square and /-tests for simple random 
variables and for ratios are used in all statistics 
with a risk coefficient of 5%. The resuhs include 
2.025 transect readings (135 runs at 15 transect 
readings each). Statistical tests follow Cochrane 
(1963). 

Observations 

Aquatic and Terrestrial Feeding 

Aquatic feeding occurrence increased from 
the end of June until the second half of July. 
Afterwards, use of aquatics dropped drastically 
during the first two weeks of August (Figure 1). 



254 



The Canadian Field-Naturalist 



Vol. 92 



--20n 



°L FEEDING MOOSE OBSERVATION 

(N:370 HOURS OF OBSERVATION) 

MEAN NO. TRACKS/ TRANSECT 

(N:2.025 TRANSECT READINGS) 




r.20 



u 

LU 

z 

.15 < 



< 
.10 ^ 

Urn 

o 



-.05 



Z 

Z 
< 



JUNE JULY JULY AUGUST AUGUST SEPTEMBER 

28-30 1-15 16-31 1-15 16-31 1-15 

Figure I. Moose observations in western Quebec during the summers of 1972 and 1973. 



No Moose were seen after this period despite 
continuous observations until 15 September. 
There was no significant difference between 
observation occurrence in June and July but 
aquatic feeding during this period is significantly 
different from that in the month of August 
{P<0.05). Furthermore, there was no signifi- 
cant difference {P>0.05) in aquatic feeding 
between different daily periods although a peak 
was noted between 1200 and 1500 hours. 

Moose spent an average (±SE) of 54 ± 18 min 
(range 5 min to 2 h 45 min, n = 18) in the water. 
Once the Moose were in the pond, only the noise 
of a passing logging truck on the road 150 m 
nearby could scare them. They paid no atten- 
tion to human voices or dogs' barking. 

The period during which feeding Moose kept 
their heads submerged was short and varied 
according to sex. The average for males was 
18 ± 2.2 s (range 5-25 s, n = 20) whereas that of 
females is 8 ± 0.7 s (range 4-1 1 s, n = 24). We 
registered a mean of 20 ± 1.7 s of mastication for 
the bulls (range 10-26 s, n = 20) and a mean of 
only 10 ± 0.7 s for the cow (range 4-12 s, 
n = 24). 

Rain affects aquatic feeding behavior. Moose 



were seen on all 20 rainless days but only four 
out of nine (44%) rainy days. 

Most terrestrial feeding was focused on only 
four species (Table 1). Mountain Maple (Acer 
spicatum) was rare whereas Pin Cherry {Prunus 
pensylvanica) was by far the most important 
species. As many as 70% of the White Birch 
stems were utilized in summer but Mountain 
Maple was the least used, with traces only. 

The highest percentage of eaten leaves (degree 
of browsing) is found on White Birch (26%) 
followed closely by willows (22%). Taking into 
account the relative density of each species, the 
percentage of stems used of each species and the 
degree of browsing, we can assume that Pin 
Cherry, because of its abundance, represented 
two-thirds of the summer Moose diet in that 
area. A fourth of the diet consisted of White 
Birch. Willows, whose presence was scanty, and 
aspen accounted for 10% each. The degree of 
browsing of willows does not vary significantly 
from that of other species (/'> 0.05) but degree 
of browsing of Trembling Aspen differs greatly 
from that of White Birch (/'< 0.01) and of Pin 
Cherry (/'<0.05; Table 1). 

Finally Moose prefer first of all White Birch 



1978 JOYAL AND SCHERRER: MOOSE IN WESTERN QUEBEC 

Table 1 — Summer moose browse analysis for Lac Laverdiere sector, Mont-Tremblant Park, Quebec 



255 



Shrub species 



Relative density Individuals Degree of Diet 

(availability) browsed (%)' browsing (%)' (%) 



Preference^ 



White Birch 

{Betula papyriferd) 
Willows 

(Salix spp.) 
Pin Cherry 

{Primus pensylvanica) 
TrembUng Aspen 

(Populus tretnulo'ides) 
Mountain Maple 

{Acer spicatum) 

Totals 



16 


70 


26'=' 


25 


1 


5 


65^' " 


22C.d.e 


6 


2 


68 


55^- 


2^'' 


65 


3 


10 


40^- 


\2'- 


4 


4 


I 


tr. 


tr. 


tr. 


5 



100 



100 



'There is no significant difference {/'>0.05) between percentage followed by same letter. 
^Preference = ratio of the proportion of the diet over the availability. 



leaves, then willow leaves. Pin Cherry, the most 
browsed species, was eaten proportionally to its 
relative abundance. 

Summer Movements 

Daily road activity is mostly nocturnal 
(Figure 2). The greatest number of tracks was 
recorded between 0000 and 0300 hours and 60% 
of the movements occurred between 2100 and 
0600 hours. The amount of movement on the 
road differs at night from movement in the day 
(P< 0.05) but no difference was found between 
each 3-h period. 

Movements varied among the different habi- 



S .2 



night 
movement 



N:2,025 readings 



12 15 



18 



21 24 
HOURS 



12 



Figure 2. Diurnal pattern of moose activity as indicated by 
the track index in Mont-Tremblant Park. 



tats as illustrated in Figure 3. The transect 
located between two ponds intercepted the 
greatest number of tracks. The least crossed 
transect was situated between a mature Sugar 
Maple {Acer saccharum) - Yellow Birch stand 
and a swamp. The difference in movement 
between these two sectors is highly significant 
(P< 0.1); however, no differences between the 
other stands are significant. 

Moose seemed to be more active on clear days, 
but no significant differences were found in 
movements between clear, cloudy, and rainy 
days. No significant difference in Moose move- 
ments in this open forest area was observed 
{P> 0.05) at various wind velocities up to 
24km/h. Winds over 24km/h reduced move- 
ment on the road and the decline in the move- 
ments was highly significant (/'<0.01). The 
highest track/ run ratio of 1.47 occurred when 
wind velocity was between 16-24 km/h (225 
readings). This ratio fell to 0.09 with winds over 
24 km/h (165 readings). 

The number of tracks per day increased from 
June to a peak in mid-July (Figure 1). From this 
date forward the frequency dropped rapidly till 
the end of August. This decUne was highly 
significant (P<0.01, 2025 readings). Figure 1 
shows the low frequency during the month of 
August and the first days of September, at which 
point we ceased observation for a week. Thus the 
activity of Moose in this study reflected the use 
of aquatics. We resumed observations on 9 
September. There was still no sign of activity on 
the entire 16-km circuit until 10 September when 



256 



The Canadian Field-Naturalist 



Vol. 92 



m 

MATURE MIXED 



m 

MATURE MIXED 
^ (128) 



Miff Ml 



CUT-OVER 




MATURE 
DECIDUOUS 



Figure 3. Movements between different habitats as indicated by the track index in Mont-Tremblant Park. 



we noticed the tracks of two Moose. The road 
was ploughed up by hooves at two different 
places and the animals had faced each other, 
suggesting a bull fight. 

Discussion 

Knorre (1959) estimated that Moose were 
active 14 h per d in summer. Direct observa- 
tions of Moose on land show that when active, 
they fed on shrubs and sometimes on forbs 
(McMillan 1954; Houston 1968). Limited direct 
observations on terrestrial activity confirmed 
these findings since we observed that Moose 
bedded for 4.5 h out of 13 h. Otherwise they 
wandered on the roads or in clear cuts, stripping 
leaves here and there while walking, or fed 
intensively on a clump of shrubs. 

Since aquatic feeding lasted about 1 h and, 
exceptionally, betweent 2 and 3 h (Dunn 1976) 



we can ascertain that terrestrial feeding formed 
the bulk of the summer diet in dry weight. Our 
conclusion differs from that of Ritcey and 
Verbeek (1969) who believed that aquatic plants 
formed the bulk of the summer diet in Bowron 
Lake Park in British Columbia. Since grazing on 
herbs and forbs was limited, we think that within 
a summer habitat study program involving 
nutritive quality for ovulation rate improve- 
ment (Markgren 1969), the nutritive quality of 
shrub leaves should be studied first. 

Moose use different shrub species in summer 
than in winter. Wintering Moose in La Veren- 
drye Park in western Quebec, showed quite a 
different order of choice, preferring willows 
most and White Birch least. Also, Mountain 
Maple was much utilized (Joyal 1976). 

The track index suggested that aquatic habitat 
was an important element of summer Moose 



1978 



JOYAL AND SCHERRER: MOOSE IN WESTERN QUEBEC 



257 



range. Radiotelemetry studies in Mastigouche 
Provincial Park in Quebec (Raymond 1978) and 
in Maine (Dunn 1976) confirmed this observa- 
tion. Furthermore, in Laurentides Park there are 
2.3 times more road kills near ponds than 
anywhere else (Grenier 1974). This correlation 
was not related to salt concentration. Studies 
should be made to determine whether aquatics 
are important for Moose and why. For example, 
a trace element essential to the maintenance of 
Moose or affecting the reproduction rate could 
be found only in certain aquatics (see Jordan et 
al. 1973). 

Most studies indicate that Moose are typically 
very active both at sunrise and sunset, and 
sometimes in the afternoon on hot humid days. 
The decline in aquatic feeding in a semi-wild area 
between 0600 and 0900 hours and a minimum of 
movement in a remote area between 1800 and 
2100 hours were quite different in our study, as 
was the peak of aquatic feeding between 1200 
and 1500 hours. Possibly the low level of early 
morning activity was due to disturbance from 
increased vehicular traffic on the nearby road 
(150 m away) as park employees went to work. 
Dunn (1976) observed that same peak of aquatic 
feeding between 1200 and 1400 in a semi-wild 
area. 

In western Minnesota, Phillips et al. (1973) 
noted that a nocturnal peak in daily movement 
of Moose is typical. In Laurentides Park in 
Quebec, 83% of Moose road kills occurred at 
night and 75% between 2000 and 0300 hours 
(Grenier 1974). Our finding that 60% of move- 
ments were nocturnal was a minimum estimate 
since tracking at night is difficult in some 
conditions, such as rainy nights. In the eastern 
part of Minnesota, however, Van Ballenberghe 
and Peek (1971) noted nearly equal movement 
between night and day for a cow and its calf. 

Our study confirms the observations of de Vos 
(1958) that aquatic feeding declined on rainy 
days. In the forest, however. Moose are 
probably less affected since neither rain nor wind 
has the same influence as in open areas like 
ponds and lakes. 

Bouchard (1967) noted that Moose used 
aquatic habitats less often when winds were 1 1 to 
18 km/h, whereas de Vos (1958) did not find 
any noticeable difference with wind up to 
16 km/h. Since we found no statistical dif- 



ference on movement with winds up to 24 km/h 
our results suggest then that wind has less 
influence on movement of Moose on the road 
than on aquatic feeding, confirming a decade of 
observation by the senior author. 

The duration of mastication not only varied 
between sexes as we observed, but also between 
individuals, as results of Bouchard (1967) 
suggest. One could hardly generalize then on the 
evaluation of aquatic intake in a study of diet for 
energy or nutrient fulfillment. Sex will have to be 
considered and a large sample of both groups 
will be needed. 

The length of time moose use aquatics 
appeared variable. In some parts of Ontario, the 
use of aquatic plants decreased gradually, 
beginning in August and ending in October (de 
Vos 1958). In Maine, ponds were also used until 
October although Dunn (1976) noted an abrupt 
decline in aquatic feeding in August. The 
behavior of our group of Moose, however, was 
similar to that studied by Bouchard (1967). In 
both cases there was a rapid decrease in the use 
of aquatics in early August ending entirely after 
mid-month. Observations during a Moose cap- 
ture program on the lakes of Mastigouche 
Provincial Park in 1975 showed the same decline 
after the first half of August (Rivard 1977). 

The complete and sudden disappearance of 
Moose during the second half of August either 
from water in 1972 or from the roads in 1973 
suggests very strongly a temporary change in 
habitat-use patterns. But this would not explain 
why Moose would return to water in mid- 
September as reported by hunters. Decline in 
plant palatability cannot be the cause of the lack 
of aquatic feeding in August. 

We believe that changes in habitat use are 
related to pre-rut activity. Many pre-rut ac- 
tivities were already observed during mid- 
August in Newfoundland 20 years ago (Dodds 
1958). In Maine, Dunn (1976) noted an impor- 
tant increase in daily movement of radio- 
equipped Moose during August. 

The bull fight is interesting because it suggests 
that by that time in western Quebec rutting 
behavior had started. According to bull harvest 
by hunting in all provincial parks, the rutting 
season, a period of greater vulnerability for 
bulls, would be earlier in western Quebec. 
Weather records for Mont-Tremblant Park 



258 



The Canadian Field-Naturalist 



Vol. 92 



during the week previous to 10 September 1973, 
indicate minima of 2°, 13°, and 12°C and 
maxima around 22°C on 7, 8, and 9 September. 
Since the first frost of the year occurred on 15 
September, the role of frost in initiating rutting 
activity seems unlikely. 

Our conclusion is that July is the best time to 
study Moose behavior by direct (visual) or 
indirect (tracks) evidence. The best habitat 
would be composed of young or immature 
mixed forest with a water body nearby. Clear 
and windless days would be better for observa- 
tion of Moose in water. Weather has less 
influence on Moose movements in the forest. 
This study suggests that movements are best 
studied at night. 

Acknowledgments 

We are indebted to Catherine Schmitt of the 
Universite de Strasbourg, France, who made the 
1972 observations; and to Roger Provost of the 
Park Service for his invaluable field assistance. 
Roger Bider is thanked for his comments on an 
early draft of the manuscript. Veronique Mor- 
neau drew the figures. Financial support was 
provided in part by National Research Council 
of Canada, grants No. A6133 (Joyal) and No. 
A9555 (Scherrer). 

Literature Cited 

Bider, J. R. 1968. Animal activity in uncontrolled ter- 
restrial communities as determined by a sand transect 
technique. Ecological Monographs 38: 269-308. 

Bouchard, R. 1967. Etude d'un habitat d'ete de I'orignal 
dans le pare des Laurentides, 1964. Service de la Faune 
du Quebec, Rapport 4: 37-58. 

Cochrane, W. 1963. Sampling techniques. Wiley and sons. 
New York. 413 pp. 

De Vos, A. 1958. Summer observations on moose behavior 
in Ontario. Journal of Mammalogy 39(1): 128 139. 

Dodds, D. G. 1958. Observations of pre-rut behavior in 
Newfoundland moose. Journal of Mammalogy 39(3): 
412-416. 

Dunn, F. 1976. Behavioral study of Moose in Maine. 
Maine Department of Inland Fisheries and Wildlife, 
Project number W66-R-6. 39 pp. 

Grenier, P. 1974. Orignaux tues sur la route dans le pare 



des Laurentides, Quebec, de 1962 a 1972. Naturaliste 
Canadien 101(5): 727-754. 

Houston, D. B. 1968. The Shiras moose in Jackson Hole, 
Wyoming. Bulletin of the Grand Teton Natural History 
Association, Technical Bulletin 1. 110 pp. 

Jordan, P. A., D. B. Botkin, A. S. Dominski, H. S. Lowen- 
dorf, and G. E. Belovsky. 1973. Sodium as a critical 
nutrient for the moose of Isle Royale. Proceedings of the 
9th North American Moose Conference and Workshop, 
Quebec, pp. 13-42. 

Joyal, R. 1976. Winter foods of moose in La Verendrye 
Park, Quebec: an evaluation of two browse survey 
methods. Canadian Journal of Zoology 54(10): 1765- 
1970. 

Knorre, E. P. 1959. Ecology of the moose. In Transactions 
of the Pechora-Illych State Game Reserve. Edited by 
G. A. Novikov. Komi Book Publishers, Syklyvkas. Can- 
adian Wildlife Service Translation Number TR-RUS-85. 
324 pp. 

Markgren, G. 1969. Reproduction of moose in Sweden. 
Viltrevy 6: 129-299. 

McMillan, J. F. 1954. Some observations on moose in 
Yellowstone Park. American Midland Naturalist 52(2): 
392-399. 

Passmore, R. C. and R. L. Hepburn. 1955. A method for 
appraisal of winter range of deer. Ontario Department 
of Land and Forests Research Report, Wildlife 29. 7 pp. 

Peek, J. M. 1974. A review of moose food habit studies in 
North America. Naturaliste Canadien 105(1-2): 195-215. 

Phillips, R. L., W. E. Berg, and D. B. Siniff. 1973. Move- 
ment patterns and range use of moose in northwestern 
Minnesota. Journal of Wildlife Management 37: 266- 
278. 

Raymond, M. 1978. Etude du domaine vital et du com- 
portement d'un orignal male dans la reserve provinciate 
de Mastigouche. M.Sc. thesis, Universite du Quebec, 
Montreal. 83 pp. 

Ritcey, R. W. and N. A. M. Verbeek. 1969. Observations 
of moose feeding on aquatics in Bowron Lake Park, 
British Columbia. Canadian Field-Naturalist 83(4): 339- 
343. 

Rivard, G. 1977. L'evaluation de diverses methodes de 
capture de I'orignal et le domaine vital d'hiver et de 
printemps determine par radio-telemetrie. M.Sc. thesis, 
Universite du Quebec, Montreal. 81 pp. 

Rowe, J. S. 1972. Les regions forestieres du Canada. 
Ministere de I'Environnement du Canada, Publication 
1300F. 172 pp. 

Van Ballenberghe, V. and J. M. Peek. 1971. Radiotele- 
metry studies of moose in northeastern Minnesota. 
Journal of Wildlife Management 35(1): 63-71. 

Received 14 March 1977 

Accepted 7 March 1978 



Asexual Reproduction, Diet, and Anomalies of the 
Anemone Nematostella vectensis in Nova Scotia 



Peter G. Frank' and J. Sherman Bleakney2 

'Invertebrate Zoology Division, National Museum of Natural Sciences, Ottawa, Ontario KIA 0M8 
^Department of Biology, Acadia University, Wolfville, Nova Scotia BOP 1X0 

Frank, Peter G. and J. Sherman Bleakney. 1978. Asexual reproduction, diet, and anomalies of the anemone Nematostella 
vectensis in Nova Scotia. Canadian Field-Naturalist 92(3); 259-263. 

Observed population increases in two aquaria containing the anemone, Nematostella vectensis, from Minas Basin, Nova 
Scotia were thought to be the result of asexual reproduction. This hypothesis was supported when 20 vitally stained and 10 
unstained anemones produced 13 new individuals, 7 of which were stained. The enteron contents of 555 anemones revealed 
nine kinds of ingested items, Hydrobia and copepods being the most common. Several anomalous forms of the anemone were 
found but no one reason for the anomalies could be demonstrated. 

Key Words: Nematostella vectensis, anemone. Nova Scotia, asexual reproduction, transverse fission, diet, anomalies. 



Nematostella vectensis is a small rare ane- 
mone of the family Edwardsiidae, first described 
from the Isle of Wight. It has since been found in 
salt marshes in other localities in England, the 
Atlantic coast of North America, and the Pacific 
coast of the United States (Crowell 1946; 
Robson 1957; Hand 1957; Bailey and Bleakney 
1966; Williams 1976). The English populations 
appear to be threatened with extinction, caused 
mainly by pollution and evaporation of their 
ponds (Williams 1976). 

Over the last few years several papers have 
appeared dealing with Nematostella vectensis 
(Williams 1973a, b, 1975, 1976; Frank and 
Bleakney 1976) and a popular account has been 
written (Lindsay 1975). The purpose of this 
paper is to describe some further aspects of the 
asexual reproduction, diet, and anomalies of the 
anemone. Specifically, we hoped to show that 
Nematostella vectensis did in fact reproduce 
asexually and this could account for a rapid 
increase in the population. The diet of A^. 
vectensis has not been reported previously. We 
also looked for anomalous forms of the 
anemone in field collections and laboratory 
experiments and compared them with those 
found by Williams (1975). 

Methods and Materials 

Anemones were collected from salt marsh 
pools at Kingsport, Nova Scotia and trans- 
ported to the laboratory where they were kept at 
room temperature in two small aquaria. The 
aquaria had been prepared by providing a 



substrate of salt-marsh pool-bottom material 
(fine flocculent mud and plant detritus), as 
previous experience had shown that the ane- 
mones would not live long on clean glass-bottom 
containers. 

Some of the anemones were stained with vital 
stains. Brilliant Cresyl Blue, Nile Blue A, and 
Safranin O, by injecting the stain into the 
enteron by hypodermic needle through the 
mouth. Usually two or three injections were 
needed to produce a color dark enough to be 
readily seen. The color persisted for about 2 wk. 

To obtain direct evidence of asexual repro- 
duction we placed 30 anemones in 10 finger 
bowls, each of which had mud and detritus on 
the bottom. Each bowl contained two vitally 
stained (one red and one blue) and one unstained 
anemone. The anemones were stained so that we 
could identify which anemones produced any 
fragments that might be found in the bowls. 
After the substrate had been added to the bowls, 
and before the experimental anemones were 
added, the bowls were left for 2 or 3 d and 
inspected regularly to make certain that any 
anemones inadvertently introduced with the 
bottom material were captured and removed. 
Therefore, any small anemones in excess of the 
three originally placed in a particular bowl 
would be the result of a reproductive process, 
and the sudden appearance of a stained fragment 
would strongly suggest asexual reproduction. 

Diet items were determined by dissecting 
preserved anemones and analyzing the enteron 
contents. 



259 



260 



The Canadian Field-Naturalist 



Vol. 92 



Results 

Asexual Reproduction 

Collections had been made during October 
and November 1972, and every month in 1973 
except February, March, and December prior to 
the experiment reported here. In many of these 
collections there were what appeared to be small 
pieces of anemones but lacking tentacles and 
pharynx. The pieces varied in size from 2 mm to 
5 mm. It was suspected that these pieces might 
be the result of asexual reproduction. 

Anemones kept in two aquaria were counted 
every day and several times there were more 
anemones than had been counted the previous 
day. Almost all of the new anemones were 
identified and all appeared to be pieces similar to 
those found in the field collections. After 3 wk, all 
of the anemones that could be seen in the two 
aquaria were removed and in both cases more 
anemones were taken out than had been put in. 
From one aquarium, to which only 20 anemones 
had been added, 29 were removed; and from the 
other which started with 18 anemones, 39 were 
removed. 

It seemed evident that the new anemones were 
the result of asexual reproduction but, to go 
beyond circumstantial evidence 10 finger bowls 
were set up, with 30 anemones 1 to 20 mm long, 
as described. Fragments began to appear within 
the first few days but they were all unstained, so 
the possibility that anemones had been buried in 
the mud could not be completely ruled out. After 
17 d, on 27 September, however, a red fragment 
was found in one of the bowls, and more colored 
fragments were found up to the end of the 
experiment. From 10 September to 15 October, 
13 fragments were produced by the 30 ane- 
mones, and 7 of these were stained. Most of them 
were 3 to 5 mm long, and the same diameter as 
the parent anemones. The fragments all pro- 
duced tentacles and a pharynx within about 2 d, 
thus conclusively showing asexual reproduction 
of A^. vectensis. The actual process was not 
witnessed and in every case took place at night. 

Diet 

Two hundred forty-two anemones collected in 
1965, 1966, and 1971 were dissected by Joan 
McCracken and the enteron contents were 
examined (unpublished report, Acadia Uni- 
versity). Of these, 32 contained 42 items: 21 
Hydrobia snails, 18 chironomid larvae, and 3 



corixid adults, suggesting that insect adults or 
larvae make up a substantial part of the 
anemones' diet. 

In the present study, 313 anemones were 
dissected with somewhat different results. In the 
74 with enteron contents, there were 1 14 items of 
eight categories, including 15 Hydrobia snails, 13 
ostracods, 40 copepods, 2 chironomid larvae, 1 1 
"worms," 18 egg masses, 14 unidentifiable 
animals (mostly crustaceans), and what ap- 
peared to be 1 rotifer test. Most of the "worms" 
were nematodes; however, some were poly- 
chaetes; the egg masses were probably from 
copepods. Although it is possible that some of 
these items were ingested accidentally, almost all 
of them showed signs ofdigestion and there were 
sufficient quantities of most of them in the 
anemones dissected to consider them regular 
prey. These data are summarized in Table 1 . 

Nematostella vectensis in the Minas Basin 
were usually found in pools with most of the 
column buried but also occurred stretched out 
on the bottom or floating in surface algae. They 
"hunted" by stretching out the tentacles until 
something made contact. Although usually 
stationary, they would sometimes tip the body in 
different directions or appear to explore the sur- 
roundings with several tentacles. 

The tentacles of N. vectensis are extremely 
responsive to tactile stimulation and immedi- 
ately wrap around anything that touches them, 
including metal probes, and draw these objects 
toward the mouth. This process was observed 
with a chironomid pupa which was placed on the 
tentacles of an anemone in the laboratory. The 
pupa was captured and drawn to the anemone's 
mouth, but it took 2 h 40 min before ingestion 
was completed. Digestion involved another 
23 h, after which the exoskeleton was ejected. 

Anomalies 

Several aberrant forms of A^. vectensis, such as 
double-headed anemones and forked tentacles, 
have been discussed by Williams (1975) for 
anemones found in England. Similar forms were 
found in the Minas Basin. The double-headed 
anemones (having a tentacled oral region at both 
ends of the body column) were more common in 
the late summer and fall, which is similar to 
Williams' findings in England (personal com- 
munication). Of nearly 1300 anemones collected 
from the Minas Basin in 1972 and 1973, 17 had 



1978 



Frank and Bleakney: Nematostella vectensis, Nova Scotia 



261 



Table 1— Food items from enteron of Nematostella vectensis. Collections were not available for February, March, and 
December. The bracketed figures are from Joan McCracken's unpublished report 



Month 



U i2 



January 

May 

June 

July 

August 

September 

October 

November 

Subtotal 
Total 



























12(8) 


20 


1 





5 





2 











18(0) 


18 


11 2 





3 


3 





1 





1 


81(0) 


81 


3(5) 





1 


3 








0(1) 





20(27) 


47 


9 29 


1 


7 


7 





5 








59(14) 


63 


3 12 








3 


12 


6 








78(0) 


78 


2(15) 2 


1(16) 














0(2) 





27(123) 


150 


0(1) 


0(2) 




















18(70) 


88 


28 46 


2 


16 


16 


14 


12 





1 


313 




(21) (0) 


(18) 


(0) 


(0) 


(0) 


(0) 


(3) 


(0) 


(242) 




49 46 


20 


16 


16 


14 


12 


3 


1 


555 





tentacles and pharynx at both ends of the body 
column, with sizes ranging from about 1 mm to 
47 mm. One Y-shaped anemone, with two 
adjacent tentacle crowns and one physa, was 
collected, and several anemones with forked 
tentacles were also found. Anemones, such as 
Wilhams' ( 1 975), found lacking tentacles or with 
a single tentacle crown and two opposing oral 
cones were not observed in the Minas Basin 
population. 

Several of the apparently normal anemones 
kept in an aquarium developed a second oral 
cone and tentacles at the physa end, and one 
double anemone placed in an aquarium resorbed 
one tentacle crown and developed a normal 
physa. 

Figure 1 shows an anemone that is just 
developing a second tentacle crown; the second 
set of tentacles is still quite small. In all other 
double anemones found, the tentacles at both 
ends of the column were of approximately equal 
sizes. Also note in Figure I that the larger 
tentacle crown is composed of 20 tentacles, the 
largest number recorded for N. vectensis. 
Previously, the maximum number reported was 
18 (Stephenson 1935). 

Discussion 

Lindsay (1975) described the transverse fis- 
sion process for A^. vectensis as beginning with 
elongation of the parent, followed by the 



development of a transverse constriction in 
the posterior portion of the column. About 24 h 
later, a new individual was formed, and tentacles 
were produced after about 2 d. Although the 
process was not actually witnessed during the 
present study, the fragmented pieces did develop 
tentacles and a pharynx within 2 d. The 
anemones in the bowls were inspected frequently 
throughout the day but persistent constrictions, 
as described by Lindsay, were not observed. 
Apparently in our study, the complete process 
took less than 24 h; in fact, the longest period the 
anemones went unobserved, excluding most 
weekends, was about 14 h. 

Asexual reproduction undoubtedly plays a 
major part in the population dynamics of A^. 
vectensis in the Minas Basin. To date, evidence 
of sexual reproduction has been reported only in 
the late summer and fall (Frank and Bleakney 
1976), but collections from pools in early spring 
and into the summer frequently contained small 
anemones and fragments, the latter identical to 
those produced in the laboratory. Williams 
(1976) observed transverse fission in January 
1975 and speculated t